Add clear instruction

- Your fork's CI will take screenshots for your fork.

Change-Id: I7ea1a437be4f9723fcf71d4d18932f8f44f46fa8

.github/workflows/Build.yaml

@@ -83,7 +83,9 @@ jobs:
         continue-on-error: false
         if: steps.screenshotsverify.outcome == 'failure' && github.event.pull_request.head.repo.full_name != github.repository
         run: |
-          echo "::error::Screenshot tests failed, please create a PR in your fork first." && exit 1
+          echo "::error::Screenshot tests failed, please create a PR in your fork first." 
+          echo "Your fork's CI will take screenshots for your fork."
+          exit 1
 
       # Runs if previous job failed
       - name: Generate new screenshots if verification failed and it's a PR