MM-9728: Online migration for advanced permissions phase 2 (#8744)

* MM-9728: Online migration for advanced permissions phase 2

* Add unit tests for new store functions.

* Move migration specific code to own file.

* Add migration state function test.

* Style fixes.

* Add i18n strings.

* Fix mocks.

* Add TestMain to migrations package tests.

* Fix typo.

* Fix review comments.

* Fix up the "Check if migration is done" check to actually work.

jobs/server.go

@@ -5,6 +5,7 @@ package jobs
 
 import (
 	ejobs "github.com/mattermost/mattermost-server/einterfaces/jobs"
+	tjobs "github.com/mattermost/mattermost-server/jobs/interfaces"
 	"github.com/mattermost/mattermost-server/model"
 	"github.com/mattermost/mattermost-server/store"
 )
@@ -34,6 +35,7 @@ type JobServer struct {
 	ElasticsearchAggregator ejobs.ElasticsearchAggregatorInterface
 	ElasticsearchIndexer    ejobs.ElasticsearchIndexerInterface
 	LdapSync                ejobs.LdapSyncInterface
+	Migrations              tjobs.MigrationsJobInterface
 }
 
 func NewJobServer(configService ConfigService, store store.Store) *JobServer {