Description of problem: Decorator for Knative revision should have route if unique route is available

Prerequisites (if any, like setup, operators/versions): Install Serverless operator

Steps to Reproduce

1. Create a ns "Sample-app"
2. Deploy an image as knative service , wait for revision to come up
3. Edit any property via edit form or yaml, wait for new revision to come to come up
4. Split traffic via context menu in topology among both revisions created above with 50-50

Actual results: can see decorator on both revisions and KSVC points to same route

Expected results: Decorator for Knative revision should have route only if unique route is available

Reproducibility (Always/Intermittent/Only Once): Always

Build Details: 4.8.0-0.nightly-2021-06-09-023740

Additional info: