[AWS|IAM] Do not call Fog.mock! in tests
[AWS|IAM] Also ignore Fog::AWS::IAM::NotFound (and return nil)
[AWS|IAM] Fix assigning path to IAM role
[AWS|IAM] Fix user count tests (there will be at least 1 other user on the account for fog access)
Merge pull request #3265 from mikehale/fix-1322

Fix 1322