Displayed actionable message when LS is not supported

[karrtikr]

For #3634

• Pull request represents a single change (i.e. not fixing disparate/unrelated things in a single PR)
• Title summarizes what is changing
• Has a news entry file (remember to thank yourself!)
• Unit tests & system/integration tests are added/updated
• Test plan is updated as appropriate
• package-lock.json has been regenerated by running npm install (if dependencies have changed)

[codecov]

Codecov Report

Merging #3864 into master will increase coverage by 3%.
The diff coverage is 89%.

@@           Coverage Diff           @@
##           master   #3864    +/-   ##
=======================================
+ Coverage      78%     81%    +3%     
=======================================
  Files         401     400     -1     
  Lines       18516   18317   -199     
  Branches     2977    2953    -24     
=======================================
+ Hits        14385   14740   +355     
+ Misses       4129    3574   -555     
- Partials        2       3     +1

Flag	Coverage Δ
#Linux	68% <62%> (ø)	⬇️
#Windows	68% <62%> (ø)	⬇️
#macOS	67% <62%> (ø)	⬇️

Impacted Files	Coverage Δ
src/client/application/diagnostics/constants.ts	100% <100%> (ø)	⬆️
src/client/activation/activationService.ts	97% <100%> (+1%)	⬆️
src/client/common/utils/localize.ts	97% <100%> (ø)	⬇️
...t/application/diagnostics/checks/lsNotSupported.ts	86% <86%> (ø)
...rc/client/common/errors/moduleNotInstalledError.ts	34% <0%> (-66%)	⬇️
src/client/linters/errorHandlers/standard.ts	40% <0%> (-55%)	⬇️
...c/client/linters/errorHandlers/baseErrorHandler.ts	78% <0%> (-22%)	⬇️
src/client/linters/errorHandlers/errorHandler.ts	78% <0%> (-22%)	⬇️
src/client/linters/errorHandlers/notInstalled.ts	45% <0%> (-16%)	⬇️
src/client/interpreter/autoSelection/proxy.ts	87% <0%> (-13%)	⬇️
... and 46 more

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Done

[d3r3kk]

Looks good. One slight adjustment you could/should make and please follow up with @DonJayamanne on the injection thing, then you should be g2g!

[DonJayamanne]

All the other diagnostic files follow the same pattern (they do not inject messageService). Should I still do it?

Yes

[DonJayamanne]

Also, @karrtikr you need to fix the merge conflicts