chore: Update validate.yml (#827)

.github/workflows/validate.yml

@@ -2,20 +2,19 @@ name: validate
 on:
   push:
     branches:
-      [
-        '+([0-9])?(.{+([0-9]),x}).x',
-        'master',
-        'next',
-        'next-major',
-        'beta',
-        'alpha',
-        '!all-contributors/**',
-      ]
-  pull_request:
-    branches-ignore: ['all-contributors/**']
+      - '+([0-9])?(.{+([0-9]),x}).x'
+      - 'master'
+      - 'next'
+      - 'next-major'
+      - 'beta'
+      - 'alpha'
+      - '!all-contributors/**'
+  pull_request: {}
 jobs:
   main:
     continue-on-error: ${{ matrix.react != 'latest' }}
+    # ignore all-contributors PRs
+    if: ${{ !contains(github.head_ref, 'all-contributors') }}
     strategy:
       matrix:
         node: [10.13, 12, 14, 15]
@@ -38,7 +37,7 @@ jobs:
       # as requested by the React team :)
       # https://reactjs.org/blog/2019/10/22/react-release-channels.html#using-the-next-channel-for-integration-testing
       - name: ⚛️ Setup react
-        run: npm install react@${{matrix.react}} react-dom@${{matrix.react}}
+        run: npm install react@${{ matrix.react }} react-dom@${{ matrix.react }}
 
       - name: ▶️ Run validate script
         run: npm run validate