core: add issue weechat#676 in ChangeLog

ChangeLog.asciidoc

@@ -29,6 +29,7 @@ https://weechat.org/files/releasenotes/ReleaseNotes-devel.html[release notes]
 [[1.5_bugs]]
 === Bugs fixed
 
+* core: fix detection of python shared libraries (issue #676)
 * api: fix number of arguments returned by function string_split() when
   keep_eol is 2 and the string ends with separators
 * irc: add missing completion "*" for target in command /msg