Advertise to already connected validators (#1790)

* Advertise to already connected validators

* Merge the loops and check the view

* Extend a test to capture new logic

* Fix a comment

* Update node/network/collator-protocol/src/collator_side.rs

Co-authored-by: Andronik Ordian <write@reusable.software>

* Update comment

Co-authored-by: Andronik Ordian <write@reusable.software>