Add skip test logic when pika not installed

[bonicim]

Description

Some tests require RMQ to be installed which in turn requires pika. When running these tests, pytest will mark those tests as 'ERROR'. If a volttron platform does not install RMQ, then running tests should not result in 'ERROR'; instead, those tests should be skipped following the example in this previous PR.

Type of change

Please delete options that are not relevant.

• [x] Bug fix (non-breaking change which fixes an issue)

How Has This Been Tested?

pytest -m vc
pytest -m vcp
pytest -m zmq
pytest -m driver

Test Configuration: Ubuntu 18.04 Python 3.10

Checklist:

• [x] My code follows the style guidelines of this project
• [x] I have performed a self-review of my own code
• [ ] I have commented my code, particularly in hard-to-understand areas
• [ ] I have made corresponding changes to the documentation
• [ ] My changes generate no new warnings
• [ ] I have added tests that prove my fix is effective or that my feature works
• [ ] New and existing unit tests pass locally with my changes
• [ ] Any dependent changes have been merged and published in downstream modules

[bonicim]

@schandrika Do these test modifications make sense to you? The intent is for these tests to skip rather than thrown an error if pika is not installed (i.e. RMQ configured on Volttron).