RFR: 7903202: enable macOS CI checks

[Maurizio Cimadamore]

On Mon, 30 May 2022 08:36:51 GMT, Denys Makogon <duke at openjdk.java.net> wrote:

> This adjustment modifies the build config by introducing
> strategy matrix in order to enable builds from both Ubuntu and macOS.

Looks good

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Marked as reviewed by mcimadamore (Committer).

PR: https://git.openjdk.java.net/jextract/pull/45