[PATCH] tests: fixed test too dependent on actual exception wording

[Georges Racinet]

# HG changeset patch
# User Georges Racinet <gracinet at anybox.fr>
# Date 1550744590 -3600
#      Thu Feb 21 11:23:10 2019 +0100
# Node ID 4170f58a6145f75e71a711886daa7439c7d4bed6
# Parent  a87ca1d7e61df30f968f5b0ca1a1f846aef91cb9
# EXP-Topic test-null-byte-filename
tests: fixed test too dependent on actual exception wording

On one of the machines I use to run the tests prior to submission,
the default Python is 2.7.5, with the following wording:

  must be encoded string without NULL bytes, not str

This third form (and possible future ones) are motivation to
use a wider catching regexp.

diff -r a87ca1d7e61d -r 4170f58a6145 tests/test-remotefilelog-gc.t
--- a/tests/test-remotefilelog-gc.t	Mon Feb 11 16:34:48 2019 +0300
+++ b/tests/test-remotefilelog-gc.t	Thu Feb 21 11:23:10 2019 +0100
@@ -108,6 +108,5 @@
 
   $ printf "asdas\0das" >> $CACHEDIR/repos
   $ hg gc
-  abort: invalid path asdas\x00da: stat: embedded null character in path (esc) (py3 !)
-  abort: invalid path asdas\x00da: stat() argument 1 must be encoded string without null bytes, not str (esc) (no-py3 !)
+  abort: invalid path asdas\x00da: .*(null|NULL).* (re)
   [255]