We have multiple tests in t5551 that write thousands of tags. To do so
efficiently we generate the tags by writing the `packed-refs` file
directly, which of course assumes that the reference database is backed
by the files backend.

Refactor the code to instead use a single `git update-ref --stdin`
command to write the tags. While the on-disk end result is not the same
as we now have a bunch of loose refs instead of a single packed-refs
file, the distinction shouldn't really matter for any of the tests that
use this helper.

Signed-off-by: Patrick Steinhardt <redacted>
---
 t/t5551-http-fetch-smart.sh | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/t/t5551-http-fetch-smart.sh b/t/t5551-http-fetch-smart.sh
index 8a41adf1e1..e069737b80 100755
--- a/t/t5551-http-fetch-smart.sh
+++ b/t/t5551-http-fetch-smart.sh

@@ -359,7 +359,9 @@ create_tags () {
 
 	# now assign tags to all the dangling commits we created above
 	tag=$(perl -e "print \"bla\" x 30") &&
-	sed -e "s|^:\([^ ]*\) \(.*\)$|\2 refs/tags/$tag-\1|" <marks >>packed-refs
+	sed -e "s|^:\([^ ]*\) \(.*\)$|create refs/tags/$tag-\1 \2|" <marks >input &&
+	git update-ref --stdin <input &&
+	rm input
 }
 
 test_expect_success 'create 2,000 tags in the repo' '

-- 
2.43.0