feat(ga-misc-check-prettier): simplify ga action

- remove creyD/prettier_action marketplace action and replace
it with two separate jobs

.github/workflows/ga-misc-check-prettier.yml

@@ -14,15 +14,15 @@ jobs:
       - name: 🐧 Checkout
         uses: actions/checkout@v3
         with:
-          ref: ${{ github.head_ref }}
-          fetch-depth: 0
+          fetch-depth: 2 # OR "2" -> To retrieve the preceding commit.
 
-      - name: 💄 Run Prettier
-        uses: creyD/prettier_action@v4.3
-        with:
-          prettier_options: --write **/*.{js,md,yml,json,sh}
-          prettier_plugins: 'prettier-plugin-sh'
-          commit_message: "chore(codebase): format with prettier"
-          only_changed: True
-        env:
-          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+      - name: Get all changed *.md file(s)
+        id: changed-md
+        run: |
+          echo "changed_files=$(git diff --name-only --merge-base master | grep "\.md$" | xargs)" >> $GITHUB_OUTPUT
+
+      - name: Run step if any *.md file(s) changed
+        if: steps.changed-md.outputs.changed_files != ''
+        run: |
+          npm i -g prettier
+          npx prettier -c ${{ steps.changed-md.outputs.changed_files }}