Beaker gssapi dependency overlap causing provisioning failures

[Dannyb48]

Describe the bug
OS: Fedora 28
python: 3.6.8
linchpin: latest

When provisioning beaker resources using the krb auth method, I get the following issues:

The full traceback is:
Traceback (most recent call last):
  File "/home/dbaez/.ansible/tmp/ansible-tmp-1579557555.6041706-150815356945781/AnsiballZ_bkr_distro_facts.py", line 102, in <module>
    _ansiballz_main()
  File "/home/dbaez/.ansible/tmp/ansible-tmp-1579557555.6041706-150815356945781/AnsiballZ_bkr_distro_facts.py", line 94, in _ansiballz_main
    invoke_module(zipped_mod, temp_path, ANSIBALLZ_PARAMS)
  File "/home/dbaez/.ansible/tmp/ansible-tmp-1579557555.6041706-150815356945781/AnsiballZ_bkr_distro_facts.py", line 40, in invoke_module
    runpy.run_module(mod_name='ansible.modules.bkr_distro_facts', init_globals=None, run_name='__main__', alter_sys=False)
  File "/usr/lib64/python3.6/runpy.py", line 208, in run_module
    return _run_code(code, {}, init_globals, run_name, mod_spec)
  File "/usr/lib64/python3.6/runpy.py", line 85, in _run_code
    exec(code, run_globals)
  File "/tmp/ansible_bkr_distro_facts_payload_i_kqhffq/ansible_bkr_distro_facts_payload.zip/ansible/modules/bkr_distro_facts.py", line 45, in <module>
  File "/tmp/ansible_bkr_distro_facts_payload_i_kqhffq/ansible_bkr_distro_facts_payload.zip/ansible/modules/bkr_distro_facts.py", line 36, in main
  File "/tmp/ansible_bkr_distro_facts_payload_i_kqhffq/ansible_bkr_distro_facts_payload.zip/ansible/modules/bkr_distro_facts.py", line 20, in __init__
  File "/home/dbaez/.virtualenvs/lp-py3/lib/python3.6/site-packages/bkr/common/hub.py", line 87, in __init__
    self._login()
  File "/home/dbaez/.virtualenvs/lp-py3/lib/python3.6/site-packages/bkr/common/hub.py", line 114, in _login
    login_method()
  File "/home/dbaez/.virtualenvs/lp-py3/lib/python3.6/site-packages/bkr/common/hub.py", line 187, in _login_krbv
    creds = gssapi.Credentials(name=name, store=store, usage='initiate')
AttributeError: module 'gssapi' has no attribute 'Credentials'

When installing beaker dependencies using pip install linchpin[beaker] in two gssapi packages are getting installed

gssapi 1.6.4
python-gssapi 0.6.4

gssapi is getting installed by beaker-client and python-gssapi is getting installed by linchpin. I believe the python-gssapi is overlapping/overwriting some libs that the gssapi library has causing issues with beaker-client. python-gssapi is an older library and not really maintained.

I have to do the following workaround to be able to provision the resource:

1. pip uninstall python-gssapi
2. pip uninstall gssapi
3. pip install gssapi

We should remove the python-gssapi from the beaker dependency install and just let beaker-client install the package it needs.

To Reproduce
Steps to reproduce the behavior:

1. pip install linchpin
2. pip install linchpin[beaker]
3. cd to a docs/workspaces/beaker
4. setup your beaker client auth to use AUTH_METHOD = krbv and KRB_REALM = REDHAT.COM
5. export BEAKER_CONF to your beaker client config
6. kinit <username>
7. linchpin -vvvv up