test(cypress): only run in parallel for pull requests

Results from pushes are not time critical.
Save some resources by avoiding the overhead of parallelization.

Signed-off-by: Max <max@nextcloud.com>

.github/workflows/cypress.yml

@@ -7,10 +7,11 @@ on:
       - main
       - master
       - stable*
+      - test/slow-cypress-on-push
 
 concurrency:
   group: ${{ github.head_ref || github.run_id }}
-  cancel-in-progress: true
+  cancel-in-progress: ${{ !github.head_ref }}
 
 env:
   APP_NAME: text
@@ -60,12 +61,6 @@ jobs:
       - name: Set up npm ${{ steps.versions.outputs.npmVersion }}
         run: npm i -g npm@"${{ steps.versions.outputs.npmVersion }}"
 
-      - name: Install dependencies & build app
-        working-directory: apps/${{ env.APP_NAME }}
-        run: |
-          npm ci
-          TESTING=true npm run build --if-present
-
       - name: Save context
         uses: actions/cache@88522ab9f39a2ea568f7027eddc7d8d8bc9d59c8 # v3.3.1
         with:
@@ -83,6 +78,23 @@ jobs:
         containers: [1, 2, 3, 4, 5, 6, 7, 8]
         php-versions: [ '8.1' ]
         server-versions: [ 'master' ]
+        is-pr:
+          - ${{ !!github.head_ref }}
+        exclude:
+          - is-pr: false
+            containers: 2
+          - is-pr: false
+            containers: 3
+          - is-pr: false
+            containers: 4
+          - is-pr: false
+            containers: 5
+          - is-pr: false
+            containers: 6
+          - is-pr: false
+            containers: 7
+          - is-pr: false
+            containers: 8
 
     name: runner ${{ matrix.containers }}
 
@@ -145,8 +157,8 @@ jobs:
       - name: Cypress run
         uses: cypress-io/github-action@v4
         with:
-          record: true
-          parallel: true
+          record: '${{ !!matrix.is-pr }}' # only on pull requests
+          parallel: '${{ !!matrix.is-pr }}' # only on pull requests
           wait-on: '${{ env.CYPRESS_baseUrl }}'
           working-directory: 'apps/${{ env.APP_NAME }}'
           config: defaultCommandTimeout=10000,video=false