Makefile cleanup

[janezpodhostnik]

Closes #???

Description

There is a bunch of old/redundant stuff in the makefile:

• mockery not actually used in this repo
• creating coverage.zip and sanderhahn/gozip old TeamCity relic. No longer used
• GOPRIVATE not used. (relic from when we had the flow-go repo in dapperlabs
• UNAME not used
• GOPATH and PATH not used. this is less obvious... CI could be using it (but its not). users might need this, but that would point to a incorrect local installation of go.

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For contributor use:

• Targeted PR against master branch
• Linked to Github issue with discussion and accepted design OR link to spec that describes this work
• Code follows the standards mentioned here
• Updated relevant documentation
• Re-reviewed Files changed in the Github PR explorer
• Added appropriate labels

[github-actions]

Dependency Review

✅ No vulnerabilities or license issues or OpenSSF Scorecard issues found.

Scanned Files

None

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.

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