Get the game working on macOS again (without PR 754 changes)

[stephengtuggy]

Thank you for submitting a pull request and becoming a contributor to the Vega Strike Core Engine.

Please answer the following:

Code Changes:

• Have the PR Validation Tests been run? See https://github.com/vegastrike/Vega-Strike-Engine-Source/wiki/Pull-Request-Validation

Issues:

• Please list any related issues
• Relates to Segmentation fault on MacOS 10.13.6 (macports) #533

Purpose:

• What is this pull request trying to do? Get the game working on macOS again, this time without all the changes from the PR 754 refactor. Also, update several of the GitHub Actions to the latest version available.
• What release is this for? 0.9.x, presumably
• Is there a project or milestone we should apply this to? 0.9.x, presumably

Additional Notes:

During play testing, I kept encountering crashes after loading certain savegames. (I think that at least some of these may be the same issue previously reported as #761 .) I also hit the crash in the Mesh destructor at least once. (#716 ) And finally, there's the issue with no text on macOS (#786)