Added symlink to generator CLI in Docker image

[ezrasingh]

Closes #15558

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• Pull Request title clearly describes the work in the pull request and Pull Request description provides details about how to validate the work. Missing information here may result in delayed response from the community.
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[wing328]

Thanks for the PR but your commit (as shown in the Commits tab) is not linked to your Github account, which means this PR won't count as your contribution in https://github.com/OpenAPITools/openapi-generator/graphs/contributors.

Let me know if you need help fixing it.

Ref: https://github.com/OpenAPITools/openapi-generator/wiki/FAQ#how-can-i-update-commits-that-are-not-linked-to-my-github-account

[wing328]

can you please also merge the latest master into your branch? we've added some tests related to Docker.

[ezrasingh]

can you please also merge the latest master into your branch? we've added some tests related to Docker.

Hey sorry y'all I just synced my fork, this PR should be ready now

[ezrasingh]

@jimschubert is it possible to merge this?