fixup! Add custom action and unified Linux build

Author: mshabunin

.github/workflows/OCV-PR-Linux.yaml

@@ -6,6 +6,12 @@ on:
       - main
     paths:
       - '.github/workflows/OCV-PR-Linux.yaml'
+      # TODO: are following paths necessary?
+      - 'checkout-and-merge/*'
+      - 'configure-and-build/*'
+      - 'run-tests/*'
+      - 'scripts/runner.py'
+      - 'scripts/test-plan.json'
   workflow_call:
     inputs:
       workflow_branch: