ci: [github-workflows] - related #388 - chromatic workflow : configur…

…e checkout action with github head ref

.github/workflows/chromatic.yml

@@ -23,6 +23,7 @@ jobs:
         uses: actions/checkout@v4
         with:
           fetch-depth: 0
+          ref: ${{ github.event.pull_request.head.ref }}
 
       - name: Setup node version
         uses: actions/setup-node@v4