Add TARGET_MACHINE.NAME header comments

[smartin015]

Description

This improves the ability to run gcode on heterogeneous print farms by indicating the machine the code is intended to run on. See #14283 for the related bug.

Type of change

• [x] New feature (non-breaking change which adds functionality)

How Has This Been Tested?

• [x] Edited tests in tests/GCodeExportTest.cpp to also confirm the presence of the new header line.

Test Configuration:

• Operating System: Ubuntu 20.04, in a docker container (see bug link for details).

Checklist:

• [x] My code follows the style guidelines of this project as described in UltiMaker Meta
• [x] I have read the Contribution guide
• [x] I have commented my code, particularly in hard-to-understand areas (N/A really)
• [x] I have uploaded any files required to test this change

[smartin015]

Looks like the test failure is something downstream of actual testing - all tests pass, but the Conclusion step in the workflow fails:

[casperlamboo]

Hi @smartin015,

I've looked at the code, and it all looks good. Ran the tests locally on my machine, and there only the LinAlg2DTest was failing, as this code did not touch any of that code the failing test is unrelated. I have tested a print by printing it, and uploading it to the digital library. In both instances the print worked as expected with the addition of the newly added comment.

Thank you for the contribution. I'm going to merge the PR, since we are in a feature freeze and have already created release branches for the 5.4 release the requested changes will be in the release after; Cura 5.5.

Thanks, Casper