Investigate webmock dependencies

[jrgriffiniii]

@elrayle successfully restored the build referenced in samvera/questioning_authority#260 by pinning webmock to release 3.6.0. In response to this, the following actions should be taken:

• Issue a PR to questioning_authority restoring the build
• Investigate other core components for this potential problem
• Explore https://github.com/bblimke/webmock in order to determine if an issue should be made for the Gem

[jrgriffiniii]

It should be noted that elrayle did find that webmock release 3.6.2 triggered failures on questioning_authority, so this may well be an upstream bug which should be resolved or documented.

[elrayle]

Update: The failures are random, so the pin of webmock did not fix this.

In QA, I tried...

• pinning webmock to 3.6.0 (latest is 3.6.2)
• pinning net-http-persistent to 3.0.1 (latest is 3.1.0)
• forcing the test app cache to regenerate

Rather or not the tests fail for any particular combination of Rails and Ruby versions appears to be random. Best I can tell, which tests fail are the same each time failures occur.

NOTE: There have been not recent changes to the tests. And the tests that are failing have been passing consistently for a long time. Some of the failing tests haven't been touched in 2 years. This definitely leads me to believe a change in dependencies or infrastructure is the cause of the failures.

[jrgriffiniii]

From what I could determine https://circleci.com/gh/samvera/questioning_authority/765 was the first failure, triggered by the merging of samvera/questioning_authority#259 on July 11th. Nothing within https://github.com/samvera/questioning_authority/pull/259/files updated any dependencies, so I would have to assume that most of the Gems (and their dependencies) in https://github.com/samvera/questioning_authority/blob/master/qa.gemspec might be suspect.

[jrgriffiniii]

I'll see about adjusting faraday versions as an experiment.