feat: add yarn.lock file

[KristianDD]

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What is the current behavior?

We don't have a yarn.lock file and this might break us if any dependency, which is dependency of our dependency and is defined with exact version, releases a breaking patch version.

What is the new behavior?

We have yarn.lock file which ensures we have consistent versions of CLI dependencies when CLI is installed with yarn.

Fixes/Implements/Closes #4103

[rosen-vladimirov]

Just ensure the file is included in the built package

[KristianDD]

@rosen-vladimirov Just checked it and grunt pack includes the yarn.lock inside the produced .tgz.