Run prettier (ethereum-lists#1551)

.github/workflows/prettier.yml

@@ -1,22 +1,24 @@
-name: Check JavaScript for conformance with Prettier
+name: Run prettier
 
 on:
-  push:
   pull_request:
 
 jobs:
   prettier:
     runs-on: ubuntu-latest
+
     steps:
-    - name: Check out repo
-      uses: actions/checkout@v2
-    - uses: actions/cache@v2
-      name: Configure npm caching
-      with:
-        path: ~/.npm
-        key: ${{ runner.os }}-npm-${{ hashFiles('**/workflows/prettier.yml') }}
-        restore-keys: |
-          ${{ runner.os }}-npm-
-    - name: Run prettier
-      run: |-
-        npx prettier --check '_data/*/*.json'	
+      - name: Checkout
+        uses: actions/checkout@v2
+        with:
+          # Make sure the actual branch is checked out when running on pull requests
+          ref: ${{ github.head_ref }}
+          # This is important to fetch the changes to the previous commit
+          fetch-depth: 0
+
+      - name: Prettify code
+        uses: creyD/[email protected]
+        with:
+          # This part is also where you can pass other options, for example:
+          prettier_options: --write _data/*/*.json
+          only_changed: True