tests: remove protected file forcibly for portability
Before this patch, test-command-template.t is timed out on Solaris,
because "rm" on permission denied file implies prompting "override
protection 0 (yes/no)?" and blocks execution of test script.
#require test-repo
$ cd "$TESTDIR"/..
New errors are not allowed. Warnings are strongly discouraged.
$ hg files "set:(**.py or **.txt) - tests/**" | sed 's|\\|/|g' |
> python contrib/check-config.py