Encryption: Improve the DX of encryption operations within database transactions (#41654)

* Move user oauth info encryption away from db transaction

* Add encryption methods with support for db session reusability

pkg/services/secrets/database/database.go

@@ -5,12 +5,10 @@ import (
 	"fmt"
 	"time"
 
-	"github.com/grafana/grafana/pkg/services/secrets"
-
-	"xorm.io/xorm"
-
 	"github.com/grafana/grafana/pkg/infra/log"
+	"github.com/grafana/grafana/pkg/services/secrets"
 	"github.com/grafana/grafana/pkg/services/sqlstore"
+	"xorm.io/xorm"
 )
 
 const dataKeysTable = "data_keys"