py3: glob out some error messages in test-fileset.t

Python3 provides more detailed messages, which is fine.

contrib/python3-whitelist

@@ -159,6 +159,7 b' test-filebranch.t'
 test-filecache.py
 test-filelog.py
 test-fileset-generated.t
+test-fileset.t
 test-fix-topology.t
 test-flags.t
 test-generaldelta.t

tests/test-fileset.t

@@ -68,7 +68,7 b' Test operators and basic patterns'
   a2
   $ fileset 'a_b'
   $ fileset '"\xy"'
-  hg: parse error: invalid \x escape
+  hg: parse error: invalid \x escape* (glob)
   [255]
 
 Test invalid syntax
@@ -196,7 +196,7 b' Test files properties'
   c1
   b1
   $ fileset 'grep("missingparens(")'
-  hg: parse error: invalid match pattern: unbalanced parenthesis
+  hg: parse error: invalid match pattern: (unbalanced parenthesis|missing \)).* (re)
   [255]
 
 #if execbit