ci: Attempt to fix prettier workflow for other user PRs (#310)

Author: DenverCoder1

.github/workflows/prettier.yml

@@ -13,8 +13,6 @@ jobs:
     steps:
       - name: Checkout
         uses: actions/checkout@v3
-        with:
-          ref: ${{ github.head_ref }}
 
       - name: Install prettier and plugin-php
         run: npm install --global prettier @prettier/plugin-php