test-hook.t: Solaris /usr/bin/egrep do not support {4} stable

test-hook.t: Solaris /usr/bin/egrep do not support {4}

--- a/tests/test-hook.t	Sun Jul 29 12:29:35 2012 -0500
+++ b/tests/test-hook.t	Mon Jul 30 02:38:29 2012 +0200
@@ -557,7 +557,7 @@
   $ echo 'precommit.importfail = python:importfail.whatever' >> .hg/hgrc
 
   $ echo a >> a
-  $ hg --traceback commit -ma 2>&1 | egrep -v '^( +File| {4}[a-zA-Z(])'
+  $ hg --traceback commit -ma 2>&1 | egrep -v '^( +File|    [a-zA-Z(])'
   exception from first failed import attempt:
   Traceback (most recent call last):
   ImportError: No module named somebogusmodule