for some reasons, tests expect the default branch to be called 'main',
while on alpine it's still 'master'.

to fix this, we can just rename the branch after cloning a test repo to 'main'.

diff --git a/Makefile b/Makefile
index 79a0407..232b001 100644
--- a/Makefile
+++ b/Makefile
@@ -478,6 +478,7 @@ test : fmt $(.DEFAULT_GOAL)
 		tempdir="$$(mktemp -d)"; \
 		export HOME="$$tempdir"; \
 		export GIT_CONFIG_NOSYSTEM=1; \
+		git config --global init.defaultBranch main; \
 		$(GO) test -count=1 $(GO_TEST_EXTRA_ARGS) $(addprefix ./,$(PKGS)); \
 		RET=$$?; \
 		chmod -R u+w "$$tempdir"; \
diff --git a/t/testhelpers.sh b/t/testhelpers.sh
index 270ca12..7624ea9 100644
--- a/t/testhelpers.sh
+++ b/t/testhelpers.sh
@@ -361,6 +361,7 @@ clone_repo() {
   echo "clone local git repository $reponame to $dir"
   out=$(git clone "$GITSERVER/$reponame" "$dir" 2>&1)
   cd "$dir"
+  git branch -m main
 
   git config credential.helper lfstest
   echo "$out" > clone.log
@@ -394,6 +395,7 @@ clone_repo_ssl() {
   echo "clone local git repository $reponame to $dir"
   out=$(git clone "$SSLGITSERVER/$reponame" "$dir" 2>&1)
   cd "$dir"
+  git branch -m main
 
   git config credential.helper lfstest
 
@@ -559,6 +561,8 @@ setup() {
   write_creds_file ":pass" "$CREDSDIR/--$certpath"
   write_creds_file ":pass" "$CREDSDIR/--$keypath"
 
+  git config --global init.defaultBranch main
+
   echo "#"
   echo "# HOME: $HOME"
   echo "# TMP: $TMPDIR"