* Add macOS support to GTKAda 21.0.0.
* Fix sed syntax for Linux.
* To be compatible between macOS and Linux, we should avoid sed -i and use tmp files instead.
* Disable problematic platforms
Co-authored-by: GHA <actions@github.com>
Also applied the rest of transformations described in alire#227: no top-level
[genera] table, name/version keys, [[depends-on]] array instead of table.
Crates without maintainer or pending migration remain in /orphaned
GitHub URLs rely on the default tarballs that at some point will
have to be released with uploaded binaries (with `alr publish` support).