Use a matrix strategy to run exam partitions

This will run partitions and parallel only after linting passes.

.github/workflows/test-ui.yml

@@ -36,7 +36,7 @@ on:
       - 'website/**'
 
 jobs:
-  test-ui:
+  lint:
     runs-on: ubuntu-latest
     timeout-minutes: 30
     steps:
@@ -47,12 +47,29 @@ jobs:
         run: cd ui && yarn run lint:js
       - name: lint:hbs
         run: cd ui && yarn run lint:hbs
-      - name: Ember tests
+  tests:
+    needs:
+      - lint
+    strategy:
+      matrix:
+        partition: [1, 2, 3, 4]
+        split: [4]
+    uses: ./.github/workflows/_ember-exam.yml
+    with:
+      partition: ${{ matrix.partition }}
+      split: ${{ matrix.split }}
+  finalize:
+    runs-on: ubuntu-latest
+    timeout-minutes: 30
+    needs:
+      - tests
+    steps:
+      - uses: actions/checkout@8e5e7e5ab8b370d6c329ec480221332ada57f0ab # v3.5.2
+      - name: yarn install
+        run: cd ui && yarn install --frozen-lockfile
+      - name: finalize
         env:
           PERCY_TOKEN: ${{ secrets.PERCY_TOKEN }}
-        run: mkdir -p /tmp/test-reports && cd ui && yarn exam
-      - uses: actions/upload-artifact@0b7f8abb1508181956e8e162db84b466c27e18ce # v3.1.2
-        with:
-          path: "/tmp/test-reports"
+        run: cd ui && yarn percy -- build:finalize
 permissions:
   contents: read