Removed invalid issuer field on valid credentials

[PatStLouis]

There is still issues with negative issuer testing, and also testing if the issuer field can be an object.

This fixes the problem where all positive tests would send an invalid issuer.

Problematic tests include:

• Testing if an issuer can be an object
• Testing if an issuer can be a http uri
• Negative testing of empty issuer field
• All description and name issuer tests