Adjust govet settings and fix issues found by it (#12947)

store/sqlstore/audit_store.go

@@ -85,9 +85,9 @@ func (s SqlAuditStore) PermanentDeleteBatch(endTime int64, limit int64) (int64,
 		return 0, model.NewAppError("SqlAuditStore.PermanentDeleteBatch", "store.sql_audit.permanent_delete_batch.app_error", nil, ""+err.Error(), http.StatusInternalServerError)
 	}
 
-	rowsAffected, err1 := sqlResult.RowsAffected()
-	if err1 != nil {
-		return 0, model.NewAppError("SqlAuditStore.PermanentDeleteBatch", "store.sql_audit.permanent_delete_batch.app_error", nil, ""+err1.Error(), http.StatusInternalServerError)
+	rowsAffected, err := sqlResult.RowsAffected()
+	if err != nil {
+		return 0, model.NewAppError("SqlAuditStore.PermanentDeleteBatch", "store.sql_audit.permanent_delete_batch.app_error", nil, ""+err.Error(), http.StatusInternalServerError)
 	}
 	return rowsAffected, nil
 }