This issue captured ideas brought up in offline discussions with @rchiodo for improving the testing experience in the repo, including faster CI time and tighter feedback loop for changes (locally)

• Shared document/kernel for test suite when appropriate. We currently open and close document for every individual test, which will launch kernel for every single. The kernel startup contributes to main portion of our CI time. When document open/close and kernels state don't matter in a test suite, we could see how we can reuse the same document and kernel for faster testing.
• A launch.json option (with properly tuned envs) to test non-conda tests locally. Currently the tests on a reasonably powerful machine takes too long and some of us rely on the CI for the test results.