Fix dap tests

[tdrwenski]

Description of Changes

Some tests were failing on GitHub unrelated to our PRs. I believe it was because testGrid was failing due to a dependence on an external resource and then not resetting a system property related to the URL encoding, and so was causing other tests to fail.

This PR adds a cleanup step for that test and also a NeedsExternalResource tag so that it won't be run on PRs.

PR Checklist

• [ ] Link to any issues that the PR addresses
• [ ] Add labels
• [ ] Open as a draft PR until ready for review
• [ ] Make sure GitHub tests pass
• [ ] Mark PR as "Ready for Review"