t/t5*: avoid redundant uses of cat

Signed-off-by: Beat Bolli <dev+git@drbeat.li>
Acked-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

t/t5100-mailinfo.sh

@@ -70,7 +70,7 @@ test_expect_success 'respect NULs' '
 
 	git mailsplit -d3 -o. "$DATA/nul-plain" &&
 	test_cmp "$DATA/nul-plain" 001 &&
-	(cat 001 | git mailinfo msg patch) &&
+	git mailinfo msg patch <001 &&
 	test_line_count = 4 patch
 
 '

t/t5317-pack-objects-filter-objects.sh

@@ -455,7 +455,7 @@ test_expect_success 'setup r1 - delete loose blobs' '
 	test_parse_ls_files_stage_oids <ls_files_result |
 	sort >expected &&
 
-	for id in `cat expected | sed "s|..|&/|"`
+	for id in `sed "s|..|&/|" expected`
 	do
 		rm r1/.git/objects/$id || return 1
 	done

t/t5534-push-signed.sh

@@ -303,7 +303,7 @@ test_expect_success GPGSM 'fail without key and heed user.signingkey x509' '
 		EOF
 		sed -n -e "s/^nonce /NONCE=/p" -e "/^$/q" dst/push-cert
 	) >expect.in &&
-	key=$(cat "${GNUPGHOME}/trustlist.txt" | cut -d" " -f1 | tr -d ":") &&
+	key=$(cut -d" " -f1 <"${GNUPGHOME}/trustlist.txt" | tr -d ":") &&
 	sed -e "s/^KEY=/KEY=${key}/" expect.in >expect &&
 
 	noop=$(git rev-parse noop) &&