Improve a bit bugzilla's version detection (#2555)

src/apps.json

@@ -1393,6 +1393,7 @@
       "html": [
         "href=\"enter_bug\\.cgi\">",
         "<main id=\"bugzilla-body\"",
+				"<a href=\"https?://www\\.bugzilla\\.org/docs/([0-9.]+)/[^>]+>Help<\\;version:\\1",
         "<span id=\"information\" class=\"header_addl_info\">version ([\\d.]+)<\\;version:\\1"
       ],
       "cookies": {