Skip a GC test known to be flaky:

  https://issues.guix.gnu.org/issue/37425
  https://github.com/golang/go/issues/27636

--- go/src/runtime/gc_test.go	2019-09-16 23:10:18.200680387 +0200
+++ go/src/runtime/gc_test.go	2019-09-16 23:11:50.324360646 +0200
@@ -27,6 +27,9 @@ func TestGcSys(t *testing.T) {
 	if runtime.GOOS == "linux" && runtime.GOARCH == "arm64" {
 		t.Skip("skipping test; GOOS=linux GOARCH=arm64 https://github.com/golang/go/issues/27636")
 	}
+	if runtime.GOOS == "linux" {
+		t.Skip("skipping test; GOOS=linux https://issues.guix.gnu.org/issue/37425")
+	}
 	got := runTestProg(t, "testprog", "GCSys")
 	want := "OK\n"
 	if got != want {
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<div class='path'>path: <a href='/guix/log/?id=13d79b64719a6dc76129b62a98d62eb86a422d20'>root</a>/<a href='/guix/log/gnu?id=13d79b64719a6dc76129b62a98d62eb86a422d20'>gnu</a>/<a href='/guix/log/gnu/packages?id=13d79b64719a6dc76129b62a98d62eb86a422d20'>packages</a>/<a href='/guix/log/gnu/packages/printers.scm?id=13d79b64719a6dc76129b62a98d62eb86a422d20'>printers.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/printers.scm?id=13d79b64719a6dc76129b62a98d62eb86a422d20&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2019-11-20 00:16:51 +0100'>2019-11-20</span></td><td><a href='/guix/commit/gnu/packages/printers.scm?id=711e8bf75fdacc8218b3957bbd7cb367da6392b5'>gnu: brlaser: Update to 6.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/printers.scm (brlaser): Update to 6.

Signed-off-by: Marius Bakke &lt;mbakke@fastmail.com&gt;
</span></span></td><td>nixo</td></tr>
<tr><td><span title='2019-04-02 22:04:08 +0200'>2019-04-02</span></td><td><a href='/guix/commit/gnu/packages/printers.scm?id=44e06f9cf39e50f91ba61f3e66981b8d10ad545c'>gnu: Add brlaser.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/printers.scm (brlaser): New variable.
</span></span></td><td>Ricardo Wurmus</td></tr>
<tr><td><span title='2018-08-30 04:42:38 +0200'>2018-08-30</span></td><td><a href='/guix/commit/gnu/packages/printers.scm?id=a82b561fef437d2f4a041e5f4df8305963552069'>gnu: robocut: Don't use unstable tarball.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/printers.scm (robocut)[source]: Use GIT-FETCH and
GIT-FILE-NAME.
</span></span></td><td>Tobias Geerinckx-Rice</td></tr>
<tr><td><span title='2018-05-13 23:16:16 +0200'>2018-05-13</span></td><td><a href='/guix/commit/gnu/packages/printers.scm?id=68fdb38f542d66d329778582c28bf7fad24324a9'>gnu: robocut: Remove unnecessary dependency on qttools.</a><span class='msg-avail'>...<span class='msg-tooltip'>Reported by Efraim Flashner.

* gnu/packages/printers.scm (robocut)[native-inputs]: Replace QTTOOLS
with QTBASE, which is where 'qmake' lives.
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2018-05-13 13:29:27 +0200'>2018-05-13</span></td><td><a href='/guix/commit/gnu/packages/printers.scm?id=d801cd0509c9c9523300c41582ec3d8e59e15539'>gnu: Add Robocut.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/printers.scm: New file.
* gnu/local.mk (GNU_SYSTEM_MODULES): Add it.
</span></span></td><td>Ludovic Courtès</td></tr>