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 <gitster@pobox.com>

Author: gitster

t/t1001-read-tree-m-2way.sh

@@ -397,7 +397,7 @@ test_expect_success 'a/b vs a, plus c/d case setup.' '
 
 test_expect_success 'a/b vs a, plus c/d case test.' '
 	read_tree_u_must_succeed -u -m "$treeH" "$treeM" &&
-	git ls-files --stage | tee >treeMcheck.out &&
+	git ls-files --stage >treeMcheck.out &&
 	test_cmp treeM.out treeMcheck.out
 '
 

t/t5523-push-upstream.sh

@@ -116,14 +116,14 @@ test_expect_success TTY 'push --no-progress suppresses progress' '
 test_expect_success TTY 'quiet push' '
 	ensure_fresh_upstream &&
 
-	test_terminal git push --quiet --no-progress upstream main 2>&1 | tee output &&
+	test_terminal git push --quiet --no-progress upstream main >output 2>&1 &&
 	test_must_be_empty output
 '
 
 test_expect_success TTY 'quiet push -u' '
 	ensure_fresh_upstream &&
 
-	test_terminal git push --quiet -u --no-progress upstream main 2>&1 | tee output &&
+	test_terminal git push --quiet -u --no-progress upstream main >output 2>&1 &&
 	test_must_be_empty output
 '