Delete all of the old kernelspecs generated by the extension

[DonJayamanne]

For #7171

[codecov-commenter]

Codecov Report

Merging #7621 (4b46625) into main (3896261) will decrease coverage by 0%.
The diff coverage is 93%.

❗ Current head 4b46625 differs from pull request most recent head d91801e. Consider uploading reports for the commit d91801e to get more accurate results

@@          Coverage Diff          @@
##            main   #7621   +/-   ##
=====================================
- Coverage     66%     66%   -1%     
=====================================
  Files        364     364           
  Lines      22558   22572   +14     
  Branches    3431    3433    +2     
=====================================
- Hits       15056   15051    -5     
- Misses      6220    6231   +11     
- Partials    1282    1290    +8     

Impacted Files	Coverage Δ
.../kernel-launcher/localKnownPathKernelSpecFinder.ts	90% <93%> (+<1%)	⬆️
src/client/pythonEnvironments/info/interpreter.ts	80% <0%> (-6%)	⬇️
src/client/datascience/jupyter/kernels/helpers.ts	64% <0%> (-6%)	⬇️
...ence/editor-integration/cellHashProviderFactory.ts	97% <0%> (-3%)	⬇️
src/client/datascience/notebook/helpers/helpers.ts	54% <0%> (-1%)	⬇️
src/client/datascience/jupyter/jupyterNotebook.ts	24% <0%> (-1%)	⬇️
...datascience/editor-integration/codelensprovider.ts	69% <0%> (+1%)	⬆️
...t/datascience/kernel-launcher/localKernelFinder.ts	85% <0%> (+2%)	⬆️

[IanMatthewHuff]

Kernel

[DonJayamanne]

I like to leave a few of these easter eggs for you.