CTS: do not continue on error

The CTS nightly stops report error because of `continue-on-error` is set
to true. Set it false such that we can know as soon as it fails.

TODO:
Temporarily change the workflow to run per-PR to verify thing is
correct. Will change it back when the PR is ready to merge.

.github/workflows/vk-gl-cts-nightly.yml

@@ -1,8 +1,12 @@
 name: VK-GL-CTS Nightly
 
 on:
-  schedule:
-    - cron: '00 07 * * *'
+  push:
+    branches: [ master ]
+  pull_request:
+    branches: [ master ]
+  # schedule:
+  #   - cron: '00 07 * * *'
 concurrency:
   group: ${{ github.workflow }}-${{ github.ref }}
   cancel-in-progress: true
@@ -12,7 +16,7 @@ jobs:
   build:
     runs-on: [Windows, self-hosted]
     timeout-minutes: 100
-    continue-on-error: true
+    continue-on-error: false
     steps:
     - uses: actions/checkout@v4
       with: