Add github macos build action.

[ymh199478]

No description provided.

[codecov-io]

Codecov Report

Merging #8 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master       #8   +/-   ##
=======================================
  Coverage   37.50%   37.50%           
=======================================
  Files           2        2           
  Lines          16       16           
=======================================
  Hits            6        6           
  Misses         10       10           

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