Move kernel execution into the 'kernels' folder

[rchiodo]

For #10152

Still more to do after this but almost have 'notebooks' out of the 'kernels' folder.

[codecov-commenter]

Codecov Report

Merging #10354 (94f287a) into main (98262a2) will decrease coverage by 0%.
The diff coverage is 76%.

@@          Coverage Diff          @@
##           main   #10354   +/-   ##
=====================================
- Coverage    64%      64%   -1%     
=====================================
  Files       212      212           
  Lines      9557     9559    +2     
  Branches   1527     1530    +3     
=====================================
- Hits       6159     6145   -14     
- Misses     2919     2935   +16     
  Partials    479      479           

Impacted Files	Coverage Δ
src/platform/common/utils.ts	70% <68%> (-2%)	⬇️
src/platform/api/kernelApi.ts	72% <100%> (-1%)	⬇️
src/platform/common/activeEditorContext.ts	93% <100%> (ø)
...rc/platform/common/dataScienceSurveyBanner.node.ts	65% <100%> (-6%)	⬇️
...rc/platform/common/extensionRecommendation.node.ts	81% <100%> (ø)
src/platform/errors/errorUtils.ts	75% <100%> (+<1%)	⬆️
...tform/interpreter/display/visibilityFilter.node.ts	91% <100%> (ø)
src/platform/common/platform/fileSystem.ts	81% <0%> (-5%)	⬇️
src/platform/errors/errorHandler.ts	63% <0%> (-3%)	⬇️