Fix a deprecation warning with newer Perl that breaks some tests.

--- a/tp/Texinfo/Parser.pm
+++ b/tp/Texinfo/Parser.pm
@@ -5438,12 +5438,12 @@
     }
   } elsif ($command eq 'clickstyle') {
     # REMACRO
-    if ($line =~ /^\s+@([[:alnum:]][[:alnum:]\-]*)({})?\s*/) {
+    if ($line =~ /^\s+@([[:alnum:]][[:alnum:]\-]*)(\{})?\s*/) {
       $args = ['@'.$1];
       $self->{'clickstyle'} = $1
         unless(_ignore_global_commands($self));
       $remaining = $line;
-      $remaining =~ s/^\s+@([[:alnum:]][[:alnum:]\-]*)({})?\s*(\@(c|comment)((\@|\s+).*)?)?//;
+      $remaining =~ s/^\s+@([[:alnum:]][[:alnum:]\-]*)(\{})?\s*(\@(c|comment)((\@|\s+).*)?)?//;
       $has_comment = 1 if (defined($4));
     } else {
       $self->line_error (sprintf($self->__(
lected'>koszko</option>
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<tr><td><span title='2019-09-30 09:49:34 +0200'>2019-09-30</span></td><td><a href='/guix/commit/gnu/packages/bison.scm?id=8d564b8b81b98fec9aac2f5f2d3cb0d1f2ea1416'>gnu: xyce: Use Bison 3.0.</a><span class='msg-avail'>...<span class='msg-tooltip'>Xyce requires Bison 3.0 at the latest.

* gnu/packages/bison.scm (bison-3.0): New variable.
* gnu/packages/engineering.scm (xyce-serial)[native-inputs]: Use
BISON-3.0 instead of BISON.
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2019-06-17 11:23:44 +0200'>2019-06-17</span></td><td><a href='/guix/commit/gnu/packages/bison.scm?id=2c35ae82192fd6f1732b15fa41aec87aa61a1879'>gnu: bison: Disable parallel tests, too.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/bison.scm (bison)[arguments]: Add #:parallel-tests?.
</span></span></td><td>Marius Bakke</td></tr>
<tr><td><span title='2019-06-16 09:39:00 +0200'>2019-06-16</span></td><td><a href='/guix/commit/gnu/packages/bison.scm?id=b1593c1c4fd8f4fc6df4c43cab51334426e3aa76'>gnu: bison: Disable parallel build.</a><span class='msg-avail'>...<span class='msg-tooltip'>Fixes &lt;https://bugs.gnu.org/36238.
Reported by Carl Dong &lt;contact@carldong.me&gt;.

* gnu/packages/bison.scm (bison)[arguments]: New field.
</span></span></td><td>Marius Bakke</td></tr>
<tr><td><span title='2019-05-25 00:47:53 +0200'>2019-05-25</span></td><td><a href='/guix/commit/gnu/packages/bison.scm?id=e7809d96aa3853e09a90c42d4b5a5dbd84765964'>gnu: bison: Update to 3.4.1.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/bison.scm (bison): Update to 3.4.1.
</span></span></td><td>Marius Bakke</td></tr>
<tr><td><span title='2019-02-07 22:10:17 +0100'>2019-02-07</span></td><td><a href='/guix/commit/gnu/packages/bison.scm?id=4ee5482a0801015f81914f1ef08b5583dc174190'>gnu: bison: Update to 3.3.2.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/bison.scm (bison): Update to 3.3.2.
</span></span></td><td>Marius Bakke</td></tr>
<tr><td><span title='2019-01-07 11:59:03 +0200'>2019-01-07</span></td><td><a href='/guix/commit/gnu/packages/bison.scm?id=3526c72c5ef0568c698f116c2aa4b614d47d77e9'>gnu: bison: Update to 3.2.4.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/bison.scm (bison): Update to 3.2.4.
</span></span></td><td>Efraim Flashner</td></tr>
<tr><td><span title='2018-12-11 23:03:27 +0100'>2018-12-11</span></td><td><a href='/guix/commit/gnu/packages/bison.scm?id=c4ac237f0898a56bcbb21e739ed4fdd51f9ac66f'>gnu: bison: Update to 3.2.2.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/bison.scm (bison): Update to 3.2.2.
</span></span></td><td>Marius Bakke</td></tr>
<tr><td><span title='2018-08-25 16:23:37 +0200'>2018-08-25</span></td><td><a href='/guix/commit/gnu/packages/bison.scm?id=cf59c62853c079938f3e415a2fb0c5821df7c607'>gnu: Remove bison@2.7.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/bison.scm (bison-2.7): Remove variable.
</span></span></td><td>Marius Bakke</td></tr>
<tr><td><span title='2018-06-12 15:06:20 +0200'>2018-06-12</span></td><td><a href='/guix/commit/gnu/packages/bison.scm?id=ac98b7a96bcd29948bd54a76cf304e3d2d90b6c4'>gnu: bison: Update to 3.0.5.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/bison.scm (bison): Update to 3.0.5.
</span></span></td><td>Tobias Geerinckx-Rice</td></tr>
<tr><td><span title='2017-03-30 01:30:16 +0200'>2017-03-30</span></td><td><a href='/guix/commit/gnu/packages/bison.scm?id=6fd52309b8f52c9bb59fccffac53e029ce94b698'>gnu: Use HTTPS for almost all gnu.org HOME-PAGEs.</a><span class='msg-avail'>...<span class='msg-tooltip'>All HTTP gnu.org (and supported subdomain) HOME-PAGEs changed to HTTPS.
</span></span></td><td>Tobias Geerinckx-Rice</td></tr>
<tr><td><span title='2016-07-29 17:35:20 +0200'>2016-07-29</span></td><td><a href='/guix/commit/gnu/packages/bison.scm?id=0160458bf8a2a77a3ec0283b4bb98fb477ed09f9'>gnu: Use define-public to export packages.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/bison.scm (bison): Define public.
* gnu/packages/flex.scm (flex): Define public.
* gnu/packages/pulseaudio.scm (libsndfile, libsamplerate, pulseaudio): Define
public.
* gnu/packages/sdl.scm (sdl, sdl2, libmikmod, sdl-gfx, sdl-image, sdl-mixer,
sdl-net, sdl-ttf): Define public.
* gnu/packages/search.scm (xapian): Remove unnecessary #:export.
* gnu/packages/swig.scm (swig): Define public.

Signed-off-by: Ludovic Courtès &lt;ludo@gnu.org&gt;
</span></span></td><td>David Craven</td></tr>
<tr><td><span title='2015-05-21 15:29:53 +0300'>2015-05-21</span></td><td><a href='/guix/commit/gnu/packages/bison.scm?id=74ed6dafb52ac10baf73aeea051a1ad2a2f0b3ac'>gnu: bison: Add m4 as a native input.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/bison (bison): Add m4 as a native input.
</span></span></td><td>Manolis Ragkousis</td></tr>