Publish GCM-Core as Trimmed self-contained executable on Linux

[kyle-rader]

Enable publishing as Trimmed on Linux

This should reduce the binary size quite substantially but will require some thorough testing.

[vtbassmatt]

This would be beneficial. I understand that .NET 6 will have even better trimming, so perhaps when we take that upgrade, we can address this.

[HumbleBee-code]

Don't want motivation because it is temporary. Be crazy about inspiration positive things

[ldennington]

To enable trimming we would need to:

1. Migrate from Newtonsoft.Json to Sytem.Text.Json in Source Generator Mode.
2. Migrate to .NET 7 where trimming is much improved.
3. Update MSAL and System.Commandline and Avalonia to the latest (preview) versions that support trimming.
4. Thorough testing.