#1737: fixed MacOS x64 release

[hohwille]

This PR fixes #1737

Implemented changes:

• fixed MacOS x64 release
• added comments to reduce the risk that this will happen again
• wanted to fix that build fails if the binary file is missing, but seems not easily possible: https://stackoverflow.com/questions/42060335/maven-assembly-fail-if-file-not-found

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Checklist for this PR

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• When running mvn clean test locally all tests pass and build is successful
• PR title is of the form #«issue-id»: «brief summary» (e.g. #921: fixed setup.bat). If no issue ID exists, title only.
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[coveralls]

Pull Request Test Coverage Report for Build 23023317637

Details

• 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 70.593%

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Totals
Change from base Build 23022840135:	0.0%
Covered Lines:	10746
Relevant Lines:	14625

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💛 - Coveralls