[MD] Delete Credential from editing page

[noCharger]

Delete single credential from its credential edit page:

A user went to the credentials view page, clicked on one credential, entered into its edit page.

Then the user clicked the delete button.

A window pops up with following context:

Delete **1 credential** permanently? 
This will also delete all their credential materials. All data sources using this credential will be invalid for access, and they must choose new credentials.

* CredentialName XXX

This action cannot be undone.

To confirm deletion, enter delete in the text input field.

After deletion confirmed, the OSD server received the delete credential request, deleted saved object and removed its credential profiles