tests: get test name automatically for remote storage

[jcsp]

Problem

Tests using remote storage have manually entered test_name parameters, which:

• Are easy to accidentally duplicate when copying code to make a new test
• Omit parameters, so don't actually create unique S3 buckets when running many tests concurrently.

Summary of changes

• Use the request fixture in neon_env_builder fixture to get the test name, then munge that into an S3 compatible bucket name.
• Remove the explicit test_name parameters to enable_remote_storage

Checklist before requesting a review

• I have performed a self-review of my code.
• If it is a core feature, I have added thorough tests.
• Do we need to implement analytics? if so did you add the relevant metrics to the dashboard?
• If this PR requires public announcement, mark it with /release-notes label and add several sentences in this section.

Checklist before merging

• Do not forget to reformat commit message to not include the above checklist

[github-actions]

1624 tests run: 1551 passed, 0 failed, 73 skipped (full report)

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_{The comment gets automatically updated with the latest test results
cf2a757 at 2023-09-01T16:13:08.282Z :recycle:}