Only catch the specific exceptions routinely thrown by the underlying code when iterating through date formats in changelog.py. Don't mask unrelated exceptions.

 - Legacy-Id: 10939

Author: levkowetz

changelog.py

@@ -23,7 +23,7 @@ def parse_date(dstr):
         try:
             t = tzparse(dstr, format)
             return t
-        except Exception:
+        except ValueError:
             pass
     raise Exception("Couldn't parse the date string '%s'" % dstr)