Make kayobe config branch input required in container promote workflow

Author: markgoddard

.github/workflows/container-promote.yml

@@ -9,7 +9,7 @@ on:
         required: false
         default: ""
       kayobe_config_branch:
-        required: false
+        required: true
         description: Branch of StackHPC Kayobe configuration to use
       check_mode:
         description: Check mode