test-acl: alter sed construct to avoid changes in .hg/hgrc formatting
A future patch is going to add some extra commented-out boilerplate to
the top of .hg/hgrc during clone. In order to make this test not
require regular updates, switch to searching for [hooks] or [acl] and
print file from the first match to that pattern.
Minimal hgk check
$ echo "[extensions]" >> $HGRCPATH
$ echo "hgk=" >> $HGRCPATH
$ hg init repo
$ cd repo
$ echo a > a
$ hg ci -Am adda
adding a
$ hg debug-cat-file commit 0
tree a0c8bcbbb45c
parent 000000000000
author test 0 0
revision 0
branch default
phase draft
adda
$ cd ..