Improve tests

[forsyth2]

Summary

This PR better structures existing tests, so it is clearer how to run each of them. It is not significantly changing what we're testing.

Objectives:

• Restructure testing directories to be clearer to follow.
• Add test assertions to test files without them (i.e., make it so output doesn't have to be manually reviewed).
• Make it so the tests files don't have to be modified to run (e.g., by changing try_# paths)
• Convert some tests to pytest (The tests in tests/integration/python_tests will require more effort to convert over).
• Change conda setup accordingly to get tests working.

Issue resolution:

• Closes [Feature]: Improve zstash testing #385

Select one: This pull request is...

• a bug fix: increment the patch version
• a small improvement: increment the minor version
• a new feature: increment the minor version
• an incompatible (non-backwards compatible) API change: increment the major version

Small Change

• To merge, I will use "Squash and merge". That is, this change should be a single commit.
• Logic: I have visually inspected the entire pull request myself.
• Pre-commit checks: All the pre-commits checks have passed.

[forsyth2]

This PR is almost exclusively test changes. Since we are in the E3SM Unified testing period, and iteratively updating tests accordingly, I'm just going to go ahead and merge this.

The only non-testing attribute changed is that the permissible versions of globus-sdk needed an upper bound to pass tests. As such, I will make a zstash rc3 after merging this PR.

[forsyth2]

Without this, we get AttributeError: 'TransferClient' object has no attribute 'endpoint_autoactivate'

[forsyth2]

This file is no longer used, as of #380.