[3.0.9 Backport] Revocation feed errors cause MultiChangesFeed to close

Revocation feed doc history fetch errors currently tear down the revocation feed and exit the overall MultiChangesFeed - resulting in clients not being able to correctly pull changes

This came from a forum post
https://forums.couchbase.com/t/never-ending-busy-state/34341/14

2022-09-15T07:50:43.862Z [WRN] c:[632d8a88] Error checking document history during revocation, seq: 81710:81708 in channel <ud>C54UWmchuGME244aGHULHn</ud>, ending revocation feed. Error: SubdocGetBodyAndXattr <ud>C54UWmchuGME244aGHULHn</ud>: Not Found – db.(*Database).buildRevokedFeed.func1() at changes.go:250
2022-09-15T07:50:43.862Z [WRN] c:[632d8a88] Error checking document history during revocation, seq: 81713:81711 in channel <ud>oAXyRKJoZ04lWw0rbXv15G</ud>, ending revocation feed. Error: SubdocGetBodyAndXattr <ud>oAXyRKJoZ04lWw0rbXv15G</ud>: Not Found – db.(*Database).buildRevokedFeed.func1() at changes.go:250

Proposed fix: If no history - don't send revocation for that doc and don't return an error entry on the changes feed that would cause the feed to close.