Python unittest discovery fails (completely)

Issue Type: Bug

1. open view "Tests" in Activity Bar
2. no tests appear, pop-up notification to configure tests
3. click on "Configure Tests"
4. select root folder, testing framework, test folder, file pattern
   ? no tests discovered
5. click "Refresh" button, GOTO step 2

VS Code version: Code 1.58.1 (2aeda6b, 2021-07-13T06:58:28.115Z)
OS version: Windows_NT x64
Restricted Mode: No

System Info

Item	Value
CPUs	Intel(R) Core(TM) i3-6006U CPU @ 2.00GHz (4 x 1992)
GPU Status	2d_canvas: enabled gpu_compositing: enabled multiple_raster_threads: enabled_on oop_rasterization: enabled opengl: enabled_on rasterization: enabled skia_renderer: enabled_on video_decode: enabled vulkan: disabled_off webgl: enabled webgl2: enabled
Load (avg)	undefined
Memory (System)	7.92GB (4.54GB free)
Process Argv	--crash-reporter-id a17b36ca-dfcd-4166-bf26-bd0a41cdc18f
Screen Reader	no
VM	0%

Extensions (10)

Extension	Author (truncated)	Version
vscode-eslint	dba	2.1.23
xml	Dot	2.5.1
vscode-dotnet-runtime	ms-	1.2.0
vscode-postgresql	ms-	0.3.0
python	ms-	2021.7.1012204448-dev
jupyter	ms-	2021.8.1013163132
vsliveshare	ms-	1.0.4568
vsliveshare-pack	ms-	0.4.0
emacs-mcx	tut	0.32.0
vscodeintellicode	Vis	1.2.14

[vscodebot]

(Experimental duplicate detection)
Thanks for submitting this issue. Please also check if it is already covered by an existing one, like:

• Test Issue (#125870)
• test (#127863)
• Test (#128365)

[connor4312]

/extPython

[vscode-triage-bot]

It looks like this is caused by the Python extension. Please file it with the repository here. Make sure to check their issue reporting template and provide them relevant information such as the extension version you're using. See also our issue reporting guidelines for more information.

Happy Coding!