Use tar with docker cp to fix various file permissions issues.

[jaklaassen-affirm]

Summary

Fixes various file permissions issues by using tar with docker cp to copy files as the sonar user.

Other Information

I believe this change is needed when using a custom workdir, but I also ran into permissions issues when using the default workdir. In my setup, the docker cp appears to overwrite file permissions with root, even though chown is run in the Dockerfile.

PR Checklist

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  The plugin version should be bumped both in .env and in the README. The plugin version is listed multiple times in the readme. Be sure to do a find/replace to ensure you haven't missed any!

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