Fix CI badge

README.md

@@ -1,4 +1,4 @@
 Source for unbl.ink website
 ===========================
 
-[![Build Status](https://ci.unbl.ink/api/badges/secstate/unbl.ink/status.svg)](https://ci.unbl.ink/secstate/unbl.ink)
+[![Build Status](https://ci.unbl.ink/api/badges/secstate/unbl.ink/status.svg?ref=refs/heads/main)](https://ci.unbl.ink/secstate/unbl.ink)