Store .vsix as part of appveyor CI

[vazexqi]

What does this PR do?

Stores the .vsix as part of the artifact for debugging purposes.

What issues does this PR fix or reference?

@W-4700676@

[vazexqi]

There seems to be a build issue that just surfaced. It looks to be related to npm/npm#19877

[codecov]

Codecov Report

Merging #322 into develop will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff            @@
##           develop     #322   +/-   ##
========================================
  Coverage    77.73%   77.73%           
========================================
  Files          127      127           
  Lines         4856     4856           
  Branches       780      780           
========================================
  Hits          3775     3775           
  Misses         888      888           
  Partials       193      193

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[vazexqi]

I followed what they have done at angular/angular-cli#9713 to fix this issue temporarily - add the dependency to a specific version of ajv at the top-level.

[vazexqi]

@guw - Artifacts are now stored and available at https://circleci.com/gh/forcedotcom/salesforcedx-vscode/218#artifacts/containers/0

@ruthemmanuelle - Just FYI, this is also a way for you to generate the .vsix yourself for installation. Just open a PR against any branch and wait for the Circle CI just to finish (no need to wait for Travis or AppVeyor) and you should be able to get the .vsix that you want.

CC: @DatGuyJonathan @lcampos - I also needed to fix the ajv issue that just popped up (not due to any of our changes). But you should be able to publish this Thursday with no issues.

[vazexqi]

As part of this work item, I realized that we don't have a proper .vscodeignore for the salesforcedx-vscode-apex-debugger and salesforcedx-vscode-lightning. This is why the size of the .vsix are larger as seen in https://ci.appveyor.com/project/guw/salesforcedx-vscode/build/develop-2008/artifacts

This happens because as part of the CI, we run the tests which will bring .vscode-test which is a binary file. This doesn't happen when we do the publishing because we use a different run (more similar to what we do in CircleCI today) which doesn't bring in the .vscode-test.

However, we can avoid this size expansion issue altogether by providing a .vscodeignore. I'll do that as part of another PR.