Allow not automatically saving files when running a test

<!-- ⚠️⚠️ Do Not Delete This! feature_request_template ⚠️⚠️ --> <!-- Please read our Rules of Conduct: https://opensource.microsoft.com/codeofconduct/ --> <!-- Please search existing issues to avoid creating duplicates. --> When a user invokes tests in VSCode that have been added through the VSCode testing API, VSCode will save some or all of the users unsaved files. For the extension I'm developing, this is undesired behavior. Our LSP server is extended with testing APIs, and it doesn't need files to be saved in order to run tests. Secondly, saving a file can trigger some heavyweight operations, and I'd only like saving to occur when our users explicitly choose to save the file. Here's the location where VSCode tries to save files when testing: https://github.com/microsoft/vscode/blob/2857051bb4e1bd7177c0d48b468b665c5a53b3c1/src/vs/workbench/contrib/testing/common/testServiceImpl.ts#L216 Could you make it so that in the [TestRunProfile](https://code.visualstudio.com/api/references/vscode-api#TestRunProfile), I can configure whether to automatically save files when this profile is run? Thanks!