CBC-10998: Added support for collapse field parameter for process search job

Pull request checklist

Please check if your PR fulfills the following requirements:

[x] Docs have been reviewed and added / updated if needed (for bug fixes / features)
[x] Tests have been added that prove the fix is effective or that the feature works.
[x] New and existing tests pass locally with the changes.
[x] Code follows the style guidelines of this project (PEP8, clean code, linter).
[x] A self-review of the code has been done.

What is the ticket or issue number?

https://jira.carbonblack.local/browse/CBC-10998

Pull Request Description

Add a collapse_field parameter to process queries.

This change was originally made by @vsvvj-cb on a forked repo, then merged into this repo as branch CBC-10998-prod-eng-test-vdp. Since that branch was made off a different version of the repository which made rebasing it onto develop impractical, I created this new branch and cherry-picked his changes onto it. The resulting code needed deflake8'ing so it would pass Codeship tests.

Does this introduce a breaking change?

[ ] Yes
[x] No

How Has This Been Tested?

Test code has been included for new feature.

carbonblack / carbon-black-cloud-sdk-python