fix node leaving the cluster to not try to trigger an election (#11242)

* bump raft version to v1.1.3

* update vendor

* transfer leadership to another node when leaving instead of removing ourselves from the cluster

* add changelog

* Update .changelog/11242.txt

Co-authored-by: Matt Keeler <mkeeler@users.noreply.github.com>

* check we can do a leadership transfer (consul 1.6.0+)

* use a const for version to check

Co-authored-by: Matt Keeler <mkeeler@users.noreply.github.com>