Make weasyprint load dynamic libraries from hard-coded path.

From NixOS
pkgs/development/python-modules/weasyprint/library-paths.patch

diff --git a/weasyprint/fonts.py b/weasyprint/fonts.py
index 377716c1..2016e01c 100644
--- a/weasyprint/fonts.py
+++ b/weasyprint/fonts.py
@@ -48,11 +48,8 @@ else:
     # with OSError: dlopen() failed to load a library: cairo / cairo-2
     # So let's hope we find the same file as cairo already did ;)
     # Same applies to pangocairo requiring pangoft2
-    fontconfig = dlopen(ffi, 'fontconfig', 'libfontconfig',
-                        'libfontconfig-1.dll',
-                        'libfontconfig.so.1', 'libfontconfig-1.dylib')
-    pangoft2 = dlopen(ffi, 'pangoft2-1.0', 'libpangoft2-1.0-0',
-                      'libpangoft2-1.0.so', 'libpangoft2-1.0.dylib')
+    fontconfig = dlopen(ffi, '@fontconfig@')
+    pangoft2 = dlopen(ffi, '@pangoft2@')
 
     ffi.cdef('''
         // FontConfig
diff --git a/weasyprint/text.py b/weasyprint/text.py
index 035074e9..08e40395 100644
--- a/weasyprint/text.py
+++ b/weasyprint/text.py
@@ -243,12 +243,9 @@ def dlopen(ffi, *names):
     return ffi.dlopen(names[0])  # pragma: no cover
 
 
-gobject = dlopen(ffi, 'gobject-2.0', 'libgobject-2.0-0', 'libgobject-2.0.so',
-                 'libgobject-2.0.dylib')
-pango = dlopen(ffi, 'pango-1.0', 'libpango-1.0-0', 'libpango-1.0.so',
-               'libpango-1.0.dylib')
-pangocairo = dlopen(ffi, 'pangocairo-1.0', 'libpangocairo-1.0-0',
-                    'libpangocairo-1.0.so', 'libpangocairo-1.0.dylib')
+gobject = dlopen(ffi, '@gobject@')
+pango = dlopen(ffi, '@pango@')
+pangocairo = dlopen(ffi, '@pangocairo@')
 
 gobject.g_type_init()
 
alue='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=a9107f2703d002bbc37c5649c6d5bcf327946d5f'>root</a>/<a href='/guix/log/po?id=a9107f2703d002bbc37c5649c6d5bcf327946d5f'>po</a>/<a href='/guix/log/po/packages?id=a9107f2703d002bbc37c5649c6d5bcf327946d5f'>packages</a>/<a href='/guix/log/po/packages/fa.po?id=a9107f2703d002bbc37c5649c6d5bcf327946d5f'>fa.po</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/po/packages/fa.po?id=a9107f2703d002bbc37c5649c6d5bcf327946d5f&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2022-07-09 21:49:34 +0200'>2022-07-09</span></td><td><a href='/guix/commit/po/packages/fa.po?id=e0d47d8facafb6d6c04741bbf30eefbc68aaefb9'>nls: Update translations.</a><span class='msg-avail'>...<span class='msg-tooltip'>po/guix/tr.po: New file.
po/guix/LINGUAS: Add it.
</span></span></td><td>Julien Lepiller</td></tr>
<tr><td><span title='2022-06-04 17:42:54 +0200'>2022-06-04</span></td><td><a href='/guix/commit/po/packages/fa.po?id=809c57c872a6dd48007d1abf6d7f3dd1482ec53a'>nls: Update translations.</a><span class='msg-avail'>...<span class='msg-tooltip'>po/packages/tr.po: New file.
po/packages/LINGUAS: Add it.
</span></span></td><td>Julien Lepiller</td></tr>
<tr><td><span title='2022-05-01 18:07:34 +0200'>2022-05-01</span></td><td><a href='/guix/commit/po/packages/fa.po?id=6b4124cdcc203d47dc40158062afa1497d73d592'>nls: Update translations.</a><span class='msg-avail'>...<span class='msg-tooltip'>po/guix/ja.po: New file.
po/guix/LINGUAS: Add it.
</span></span></td><td>Julien Lepiller</td></tr>
<tr><td><span title='2022-04-02 18:42:36 +0200'>2022-04-02</span></td><td><a href='/guix/commit/po/packages/fa.po?id=8a208df17fe81fbf34f5a86cc52bb0b8e33c7b96'>nls: Update translations.</a><span class='msg-avail'>...<span class='msg-tooltip'>* po/packages/fi.po: New file.
* po/packages/LINGUAS: Add it.
</span></span></td><td>Julien Lepiller</td></tr>
<tr><td><span title='2021-04-18 13:18:17 +0200'>2021-04-18</span></td><td><a href='/guix/commit/po/packages/fa.po?id=43fb84da6749a78d12ac0f13db4cecb435de7903'>nls: Add Persian translation.</a><span class='msg-avail'>...<span class='msg-tooltip'>* po/packages/fa.po: New file.
* po/packages/LINGUAS: Add 'fa'.
* po/doc/guix-cookbook.fa.po: New file.
* po/doc/guix-manual.fa.po: New file.
* po/doc/local.mk (DOC_PO_FILES, DOC_COOKBOOK_PO_FILES): Add them.
* doc/local.mk (info_TEXINFOS): Add them.
</span></span></td><td>Julien Lepiller</td></tr>