ci: reverting dockerfiles due to docker bug

[wass3r]

❤ THANKS FOR HELPING OUT :D

Proposed change

Noticed an issue during the docker image build. Apparently there's a bug with multiple successive COPY statements in Docker that we're affected by, see moby/moby/issues/37965 . Instead of applying known workaround, reverting Dockerfiles back to old setup w/ some tweaks.

Types of changes

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• Bugfix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)

Checklist

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• I have added tests that prove my fix is effective or that my feature works
• I have added necessary documentation (if appropriate)

[github-actions]

Pull Request Test Coverage Report for Build 6a8613077004fc8ba135479cc1062de9a38c125d-PR-137

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 42.238%

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Totals
Change from base Build c6aed2f77966a8e3b86120575a4baaf45ef51370:	0.0%
Covered Lines:	770
Relevant Lines:	1823

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💛 - Coveralls