t/t3800-mktag.sh: use test_must_fail rather than '!'

diff --git a/t/t5505-remote.sh b/t/t5505-remote.sh
index 636aec2f7139cad63591d64e8c89e82d2ed4760b..4fc62f550cbced0f1e257fa5057e43f4c54ed5dd 100755 (executable)
--- a/t/t5505-remote.sh
+++ b/t/t5505-remote.sh
@@ -4,9 +4,6 @@ test_description='git remote porcelain-ish'
 
 . ./test-lib.sh
 
-GIT_CONFIG=.git/config
-export GIT_CONFIG
-
 setup_repository () {
        mkdir "$1" && (
        cd "$1" &&