Mirror does not update when initial default branch is an arbitrary name, not master

Summary

Before the first push to a newly created repository, rename the local default branch from "master" to an arbitrary name i.e "test".
When you push to remote, check the UI, this error is received "The default branch is set to "refs/heads/master" but does not exist. Configure the default branch in the repository settings."

After changing the default branch to "test", when you try to clone from the mirror, you get the error "warning: remote HEAD refers to nonexistent ref, unable to checkout.", but cloning from the upstream server works fine.

Steps to reproduce

mkdir test
cd test
git init
echo "Test word" > index.txt
git add index.txt
git commit -m "added index.txt"
git branch -m master test
git remote add origin https://upstream_server.com/scm/bpr/test.git
git push --set-upstream origin test

Try to clone from the mirror

git clone https://mirror_server.com/scm/bpr/test.git
Cloning into 'test'...
remote: Enumerating objects: 3, done.
remote: Counting objects: 100% (3/3), done.
remote: Total 3 (delta 0), reused 0 (delta 0)
Unpacking objects: 100% (3/3), done.
warning: remote HEAD refers to nonexistent ref, unable to checkout.

Workaround

Navigate to the repository in the mirror file system, and manually updated the default branch from the "HEAD" file: from ref: refs/heads/master to ref: refs/heads/test