Add MSSQL to supported database list of intall page (#3359)

Author: sapk

options/locale/locale_en-US.ini

@@ -63,7 +63,7 @@ cancel = Cancel
 install = Installation
 title = Initial configuration
 docker_helper = If you are running Gitea inside Docker, please read the <a target="_blank" rel="noopener" href="%s">guidelines</a> carefully before changing anything on this page.
-requite_db_desc = Gitea requires MySQL, PostgreSQL, SQLite3, or TiDB.
+requite_db_desc = Gitea requires MySQL, MSSQL, PostgreSQL, SQLite3, or TiDB.
 db_title = Database Settings
 db_type = Database Type
 host = Host