MM-53228: Adding schema version to cluster info (#24209)

With the schema version available, a job can query for
the cluster info to confirm whether or not all nodes
in a cluster are upgraded to the same version or not.

This will help it in determining whether to start
the job or not.

https://mattermost.atlassian.net/browse/MM-53228

```release-note
NONE
```

server/channels/store/store.go

@@ -67,6 +67,7 @@ type Store interface {
 	DropAllTables()
 	RecycleDBConnections(d time.Duration)
 	GetDBSchemaVersion() (int, error)
+	GetLocalSchemaVersion() (int, error)
 	GetAppliedMigrations() ([]model.AppliedMigration, error)
 	GetDbVersion(numerical bool) (string, error)
 	// GetInternalMasterDB allows access to the raw master DB