Cannot associate a database with account (plugin)

[jcervantes-sipecom]

• Version of the plugin :
  2.3.2

• Version of your GLPI :
  9.5.7

• Steps to reproduce (which actions have you made) :

1. Go to the created database
2. Clic to Associated Element
3. Account plugin didn't appear in the dropdown list.

• Expected result :
  A database should be possible to associate with a account

• Actual result :
  A database cannot be to associate with a account

Reference to issue in account plugin: InfotelGLPI/accounts#83