[CI] Turned On NightlyTests on PR

The self-hosted runners inexplicably came back to life. Turning back on
the NightlyTests on PR synchronization.

Author: AlexandreSinger

.github/workflows/nightly_test.yml

@@ -1,6 +1,23 @@
 name: NightlyTest
 
 on:
+  # We want to run the CI when anything is pushed to master.
+  # Since master is a protected branch this only happens when a PR is merged.
+  # This is a double check in case the PR was stale and had some issues.
+  push:
+    branches:
+      - master
+    paths-ignore: # Prevents from running if only docs are updated
+      - 'doc/**'
+      - '**/*README*'
+      - '**.md'
+      - '**.rst'
+  pull_request:
+    paths-ignore: # Prevents from running if only docs are updated
+      - 'doc/**'
+      - '**/*README*'
+      - '**.md'
+      - '**.rst'
   workflow_dispatch:
   schedule:
   - cron: '0 0 * * *' # daily