tests: drop use of 'tee' that hides exit status

tests: drop use of 'tee' that hides exit status

A few tests have "| tee output" downstream of a git command, and
then inspect the contents of the file.  The net effect is that we
use an extra process, and hide the exit status from the upstream git
command.

In any of these tests, I do not see a reason why we want to hide a
possible failure from these git commands.  Replace the use of tee
with a plain simple redirection.

Signed-off-by: Junio C Hamano <redacted>