BUILD-10889 Fix unified dogfooding workflow

Author: hedinasr

.github/workflows/unified-dogfooding.yml

@@ -1,5 +1,8 @@
 name: Unified Dogfooding scans
 on:
+  pull_request:
+    branches:
+      - master
   schedule:
     - cron: "0 4 * * 1-5" # Run the workflow Mon-Fri at 04:00 UTC
   workflow_dispatch:
@@ -26,7 +29,7 @@ jobs:
           artifactory-deployer-role: qa-deployer
           scanner-java-opts: '-Xmx2g'
       - name: Run IRIS Analysis
-        uses: SonarSource/unified-dogfooding-actions/run-iris@v1
+        uses: SonarSource/unified-dogfooding-actions/run-iris@master
         with:
           primary_project_key: org.sonarsource.java:java
           primary_platform: "Next"