Bugfix release version 0.2.1

[awvwgk]

The various build system patches after the 0.2.0 release might warrant a small bugfix release. Please create a new tag v0.2.1 if merged.

[kjelljorner]

Would be great to have this approved and merged as these build problems current prevent me from deploying libconeangle to osx arm64 on conda-forge.

[ivan-pi]

Do I get this right, after merging I just need to go to the release page (https://github.com/fortran-lang/stdlib/releases) and click on "Draft a new release" and copy-paste (and adapt) the CHANGELOG for the Release description?

[awvwgk]

You can also autogenerate the release notes from the merged pull requests (there is a button on the top right), this is what @jvdp1 did for the v0.2.0 release.

[milancurcic]

Done, it was very easy. Thanks @awvwgk for guiding.

[awvwgk]

For future reference, here is the release guide for fpm: https://github.com/fortran-lang/fpm/wiki/Release-Process, we might create something similar for stdlib, especially for the release aftermath.