tests: convert the 'file://\$TESTTMP' rule to an automatic substitution
The rule only triggered on non Windows platforms, even though Windows also
required an adjustment. Automatic seems better.
The aggressive globbing in test-subrepo-svn.t was found and rewritten by the
substitution.
#require clang-format test-repo
$ . "$TESTDIR/helpers-testrepo.sh"
$ cd "$TESTDIR"/..
$ for f in `testrepohg files 'set:(**.c or **.h) and not "listfile:contrib/clang-format-blacklist"'` ; do
> clang-format --style file $f > $f.formatted
> cmp $f $f.formatted || diff -u $f $f.formatted
> rm $f.formatted
> done