Tweak workflow

Author: rawilk

.github/workflows/markdown-normalize.yml

@@ -15,6 +15,8 @@ jobs:
         steps:
             -   name: Git checkout
                 uses: actions/checkout@v3
+                with:
+                    ref: ${{ github.head_ref }}
 
             -   name: Prettify markdown
                 uses: creyD/[email protected]