Improve issue search (#2387)

* Improve issue indexer

* Fix new issue sqlite bug

* Different test indexer paths for each db

* Add integration indexer paths to make clean

.gitignore

@@ -53,5 +53,8 @@ coverage.all
 /integrations/gitea-integration-mysql
 /integrations/gitea-integration-pgsql
 /integrations/gitea-integration-sqlite
+/integrations/indexers-mysql
+/integrations/indexers-pgsql
+/integrations/indexers-sqlite
 /integrations/mysql.ini
 /integrations/pgsql.ini