chore: remove sqlstore & mockstore dependencies from (most) packages (#57087)

* chore: add alias for InitTestDB and Session

Adds an alias for the sqlstore InitTestDB and Session, and updates tests using these to reduce dependencies on the sqlstore.Store.

* next pass of removing sqlstore imports
* last little bit
* remove mockstore where possible

pkg/services/export/export_usage.go

@@ -6,11 +6,12 @@ import (
 	"strings"
 
 	"github.com/grafana/grafana-plugin-sdk-go/data/sqlutil"
-	"github.com/grafana/grafana/pkg/services/sqlstore"
+
+	"github.com/grafana/grafana/pkg/infra/db"
 )
 
 func exportUsage(helper *commitHelper, job *gitExportJob) error {
-	return job.sql.WithDbSession(helper.ctx, func(sess *sqlstore.DBSession) error {
+	return job.sql.WithDbSession(helper.ctx, func(sess *db.Session) error {
 		commit := commitOptions{
 			comment: "usage stats",
 		}