Credential select box does not always contains option to create new

[3keyroman]

Describe the bug
When the Credential should be selected from the attribute, it should contain option to create new Credential using the + button. The purpose of this button is to create new Credential and select it without having to leave the form and continue. However, this works only in case the attribute name is set to credential. Attributes with the same Credential content type but with different name does not show the + button.

To Reproduce
Steps to reproduce the behavior:

1. Go to Discovery
2. Create new CT logs discovery
3. API Key contains list without + button

Expected behavior
All attributes with Credential content type should provide option to create new credential without leaving the form. Not only those that has name credential.

Additional context
Teste on the version 2.13.0