Update tests

[kurtmckee]

This PR overhauls the test suite in several ways:

• All tests are parametrized where possible -- tests no longer use for loops.

  This has resulted in a jump in test visibility from 171 tests to 307 tests.

• The jsonpath_ng and jsonpath_ng.ext parsers are now tested in lock step -- inconsistently quadruplicated test cases have been consolidated.

• Fixtures have been introduced to control auto_id.

• The test suite is now at 100% code coverage.

• pytest-randomly has been introduced to randomize the order of test modules and test cases, which helps demonstrate that tests are fully isolated from each other.

All files have been run through black, isort, and pyupgrade.

[kurtmckee]

@michaelmior It appears that the current merge strategy is breaking all of my commit signatures and causing them to be marked as "Unverified":

Commits in every PR

Commits after merging

Is it possible to merge PRs without rewriting the git history? I don't know if this is being enforced by a repo setting like "Require a linear git history" or some such, but wanted to ask.

[michaelmior]

I prefer keeping linear history where possible. If you want your commits to show as verified, the easiest way to have both these happen is to make sure that your PR is rebased on the latest master branch.

[kurtmckee]

make sure that your PR is rebased on the latest master branch

#143 was based on then-current master and all of the commits were still rewritten. It appears that the current merge strategy -- at least as it's currently implemented -- consistently but unnecessarily rewrites commits.

Would you consider forgoing your preference for a linear history?

[michaelmior]

@kurtmckee Personally I find the benefit of a linear history greater than the benefit of verified commits.

[kurtmckee]

Okay.