Moving mlog to corelibs (#16915)

* Moving mlog to corelibs

* Regenerating app layers

* Fix golangci-lint problem

* Fixing golangci-lint errors

* Renaming from corelibs to shared

* Renaming from corelibs to shared

* Fixing import

* Fixing merge problems

* Fixing build

api4/apitestlib.go

@@ -23,9 +23,9 @@ import (
 
 	"github.com/mattermost/mattermost-server/v5/app"
 	"github.com/mattermost/mattermost-server/v5/config"
-	"github.com/mattermost/mattermost-server/v5/mlog"
 	"github.com/mattermost/mattermost-server/v5/model"
 	"github.com/mattermost/mattermost-server/v5/services/searchengine"
+	"github.com/mattermost/mattermost-server/v5/shared/mlog"
 	"github.com/mattermost/mattermost-server/v5/store"
 	"github.com/mattermost/mattermost-server/v5/store/localcachelayer"
 	"github.com/mattermost/mattermost-server/v5/store/storetest/mocks"