refactor: Remove duplicate user index

Signed-off-by: Corey <[email protected]>

Author: cbaker6

src/Controllers/DatabaseController.js

@@ -1706,12 +1706,6 @@ class DatabaseController {
       throw error;
     });
 
-    await this.adapter
-      .ensureIndex('_User', requiredUserFields, ['username'], 'case_insensitive_username', true)
-      .catch(error => {
-        logger.warn('Unable to create case insensitive username index: ', error);
-        throw error;
-      });
     await this.adapter
       .ensureIndex('_User', requiredUserFields, ['username'], 'case_insensitive_username', true)
       .catch(error => {