headers: normalize the spelling of some header guards

diff --git a/t/t5523-push-upstream.sh b/t/t5523-push-upstream.sh
index d6981ba304b0b1f2da22d8ec14d4b472b54f3415..c0df81a014c360c277f38831a37cb6f9c4e9bad7 100755 (executable)
--- a/t/t5523-push-upstream.sh
+++ b/t/t5523-push-upstream.sh
@@ -113,7 +113,7 @@ test_expect_success TTY 'quiet push' '
        ensure_fresh_upstream &&
 
        test_terminal git push --quiet --no-progress upstream master 2>&1 | tee output &&
-       test_cmp /dev/null output
+       test_must_be_empty output
 '
 
 test_done