Work around two test suite failures on ARM:

  https://github.com/ruby-concurrency/concurrent-ruby/issues/547

The regexps here assume addresses like "0x1234" but on ARM (32-bit)
we get something like "0x-7db1e810" (notice the dash).

diff --git a/spec/concurrent/edge/promises_spec.rb b/spec/concurrent/edge/promises_spec.rb
index 727210f..149f7cd 100644
--- a/spec/concurrent/edge/promises_spec.rb
+++ b/spec/concurrent/edge/promises_spec.rb
@@ -371,9 +371,9 @@ describe 'Concurrent::Promises' do
       four  = three.delay.then(&:succ)
 
       # meaningful to_s and inspect defined for Future and Promise
-      expect(head.to_s).to match /<#Concurrent::Promises::Future:0x[\da-f]+ pending>/
+      expect(head.to_s).to match /<#Concurrent::Promises::Future:0x-?[\da-f]+ pending>/
       expect(head.inspect).to(
-          match(/<#Concurrent::Promises::Future:0x[\da-f]+ pending>/))
+          match(/<#Concurrent::Promises::Future:0x-?[\da-f]+ pending>/))
 
       # evaluates only up to three, four is left unevaluated
       expect(three.value!).to eq 3
diff --git a/spec/concurrent/map_spec.rb b/spec/concurrent/map_spec.rb
index c4050be..0a9095d 100644
--- a/spec/concurrent/map_spec.rb
+++ b/spec/concurrent/map_spec.rb
@@ -794,7 +794,7 @@ module Concurrent
     end
 
     it '#inspect' do
-      regexp = /\A#<Concurrent::Map:0x[0-9a-f]+ entries=[0-9]+ default_proc=.*>\Z/i
+      regexp = /\A#<Concurrent::Map:0x-?[0-9a-f]+ entries=[0-9]+ default_proc=.*>\Z/i
       expect(Concurrent::Map.new.inspect).to match(regexp)
       expect((Concurrent::Map.new {}).inspect).to match(regexp)
       map = Concurrent::Map.new
'3211f45f0b741d5dea97de3745804881d7446d34'/><select name='qt'>
<option value='grep'>log msg</option>
<option value='author'>author</option>
<option value='committer'>committer</option>
<option value='range'>range</option>
</select>
<input class='txt' type='search' size='10' name='q' value=''/>
<input type='submit' value='search'/>
</form>
</td></tr></table>
<div class='path'>path: <a href='/guix/log/?id=3211f45f0b741d5dea97de3745804881d7446d34'>root</a>/<a href='/guix/log/gnu?id=3211f45f0b741d5dea97de3745804881d7446d34'>gnu</a>/<a href='/guix/log/gnu/packages?id=3211f45f0b741d5dea97de3745804881d7446d34'>packages</a>/<a href='/guix/log/gnu/packages/vim.scm?id=3211f45f0b741d5dea97de3745804881d7446d34'>vim.scm</a></div><div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/guix/log/gnu/packages/vim.scm?id=3211f45f0b741d5dea97de3745804881d7446d34&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2019-03-18 15:05:08 +0100'>2019-03-18</span></td><td><a href='/guix/commit/gnu/packages/vim.scm?id=47956fa0c24efcdcba3493f0231c30e9a39ec7df'>Correct name and email address for ng0.</a><span class='msg-avail'>...</span></td><td>ng0</td></tr>
<tr><td><span title='2019-03-17 20:33:21 +0200'>2019-03-17</span></td><td><a href='/guix/commit/gnu/packages/vim.scm?id=de3ed0b4d4e15409fcd5c1679488f34fba44912f'>gnu: Add editorconfig-vim.</a><span class='msg-avail'>...</span></td><td>Efraim Flashner</td></tr>
<tr><td><span title='2019-03-07 13:39:45 +0100'>2019-03-07</span></td><td><a href='/guix/commit/gnu/packages/vim.scm?id=3189fad217e257fb9bef3e632a3f7b36ae05748a'>gnu: neovim: Let build phase return #T.</a><span class='msg-avail'>...</span></td><td>Ricardo Wurmus</td></tr>
<tr><td><span title='2019-03-07 11:08:31 +0100'>2019-03-07</span></td><td><a href='/guix/commit/gnu/packages/vim.scm?id=0a10abf73e7bb1d5f751229c709903a0f66574d2'>gnu: neovim: Fix #34616.</a><span class='msg-avail'>...</span></td><td>Gábor Boskovits</td></tr>
<tr><td><span title='2019-02-17 10:28:13 +0100'>2019-02-17</span></td><td><a href='/guix/commit/gnu/packages/vim.scm?id=52bc70e42d4da8901d6093b276822e783a76853a'>gnu: neovim: Update to 0.3.4.</a><span class='msg-avail'>...</span></td><td>Danny O'Brien</td></tr>
<tr><td><span title='2019-02-13 21:48:10 +0200'>2019-02-13</span></td><td><a href='/guix/commit/gnu/packages/vim.scm?id=28388ac8f8dedd1984379119e480ecbd10c6fc30'>gnu: vim-airline: Update to 0.10.</a><span class='msg-avail'>...</span></td><td>Efraim Flashner</td></tr>
<tr><td><span title='2018-12-29 20:26:45 +0200'>2018-12-29</span></td><td><a href='/guix/commit/gnu/packages/vim.scm?id=9123c420ddb420ccfb72d03feb76250f54374f9e'>gnu: vim: Update to 8.1.0644.</a><span class='msg-avail'>...</span></td><td>Efraim Flashner</td></tr>
<tr><td><span title='2018-12-29 20:26:45 +0200'>2018-12-29</span></td><td><a href='/guix/commit/gnu/packages/vim.scm?id=597f35e6f02eccdb4a010472940f642183ed2325'>gnu: vim-full: Fix test suite.</a><span class='msg-avail'>...</span></td><td>Efraim Flashner</td></tr>
<tr><td><span title='2018-12-27 15:34:02 +0200'>2018-12-27</span></td><td><a href='/guix/commit/gnu/packages/vim.scm?id=b130354999bf37ae5f155dbea1a9c57a0861b707'>gnu: vim: Don't use unstable tarball.</a><span class='msg-avail'>...</span></td><td>Efraim Flashner</td></tr>
<tr><td><span title='2018-12-27 15:34:02 +0200'>2018-12-27</span></td><td><a href='/guix/commit/gnu/packages/vim.scm?id=3d6bc5af91b522a81e3b157b1dfefa66d9e7adf8'>gnu: vim: Use https.</a><span class='msg-avail'>...</span></td><td>Efraim Flashner</td></tr>
<tr><td><span title='2018-12-01 18:48:54 +0200'>2018-12-01</span></td><td><a href='/guix/commit/gnu/packages/vim.scm?id=fb0b645658041c3061d2f70dc1a11a100f569217'>gnu: vim-fugitive: Update to 2.5.</a><span class='msg-avail'>...</span></td><td>Efraim Flashner</td></tr>
<tr><td><span title='2018-11-30 00:21:26 -0600'>2018-11-30</span></td><td><a href='/guix/commit/gnu/packages/vim.scm?id=4168e3faf2f4354fe4e469b67dc276e5374d20ad'>neovim: Update to 0.3.1.</a><span class='msg-avail'>...</span></td><td>Eric Bavier</td></tr>
<tr><td><span title='2018-11-29 15:45:44 +0100'>2018-11-29</span></td><td><a href='/guix/commit/gnu/packages/vim.scm?id=7af6e5daa4ffb1bbda48a4e990815066f21bdadc'>gnu: vim: Update to 8.1.0551.</a><span class='msg-avail'>...</span></td><td>Marius Bakke</td></tr>
<tr><td><span title='2018-11-12 12:37:00 +0200'>2018-11-12</span></td><td><a href='/guix/commit/gnu/packages/vim.scm?id=53bcee9ea7e885e756ad4689381aa2bdfbac97ef'>gnu: vifm: Update to 0.10.</a><span class='msg-avail'>...</span></td><td>Efraim Flashner</td></tr>