Caching: Implement mtls-enabled memcached integration (#84171)

* fix merge

* fix conflicts

* updating generated feature toggle code

* Fix go mod owner

* fix merge

* add dependency

* fix dependencies

* workspace sync

* go get

* work sync

* trying something

* fix

* add docs for tls config

* work sync

* adjust go mod

* try something

* move import to the correct file

---------

Co-authored-by: Michael Mandrus <michael.mandrus@grafana.com>

go.mod

@@ -48,6 +48,7 @@ require (
 	github.com/blugelabs/bluge v0.1.9 // @grafana/grafana-backend-group
 	github.com/blugelabs/bluge_segment_api v0.2.0 // @grafana/grafana-backend-group
 	github.com/bradfitz/gomemcache v0.0.0-20190913173617-a41fca850d0b // @grafana/grafana-backend-group
+	github.com/grafana/gomemcache v0.0.0-20231023152154-6947259a0586 // @grafana/grafana-operator-experience-squad
 	github.com/bufbuild/connect-go v1.10.0 // @grafana/observability-traces-and-profiling
 	github.com/bwmarrin/snowflake v0.3.0 // @grafan/grafana-app-platform-squad
 	github.com/centrifugal/centrifuge v0.30.2 // @grafana/grafana-app-platform-squad