Description of problem:
When we do brute force password attack via hammer (min. 30 trying), it returns the message "Invalid username or password." 
After that we put a correct credential, but hammer/API still return the same message "Invalid username or password.". It is little confusing. 

Version-Release number of selected component (if applicable):
Sat6.4#11

How reproducible:
100%

Steps to Reproduce:
1. We have got Sat6.4 and client machine.
2. We register the client machine to Satellite 6.4 repo and install hammer (standalone)
  > yum install -y tfm-rubygem-hammer_cli_katello
  > hammer --fetch-ca-cert https://satellite.example.com/
  > install /root/.hammer/certs/satellite.example.com_443.pem /etc/pki/ca-trust/source/anchors/
  > update-ca-trust

3. Check hammer
> hammer -u admin -p correct_password user list
...

4. Brute force password attack
> for i in {1..30}; do hammer -u admin -p bad_password user list; done
Invalid username or password.
Invalid username or password.
...
Invalid username or password.
Invalid username or password.

5. Check hammer with the correct password
> hammer -u admin -p correct_password user list

Actual results:
we get the message "Invalid username or password."

Expected results:
We should get the message "Too many tries, please try again in a few minutes.". The same as via WebUI.


Additional info:
> hammer -d -u admin -p correct_password user list
...
[DEBUG 2018-07-18T04:58:00 API] Using authenticator: HammerCLIForeman::Api::InteractiveBasicAuth
[ERROR 2018-07-18T04:58:00 API] 401 Unauthorized
[DEBUG 2018-07-18T04:58:00 API] {
    "error" => {
        "message" => "Unable to authenticate user "
    }
}
[DEBUG 2018-07-18T04:58:00 Exception] Using exception handler HammerCLIForeman::ExceptionHandler#handle_foreman_unauthorized
[ERROR 2018-07-18T04:58:00 Exception] Invalid username or password.
Invalid username or password.
[ERROR 2018-07-18T04:58:00 Exception] 

HammerCLIForeman::Api::UnauthorizedError (Invalid username or password.):
...