[release candidate] pantsbuild.pants 1.30.3rc0

[John Sirois]

The first release candidate for 1.30.3 is now available on PyPI.

See here for a summary of the 1.30.x series and a link to a more detailed changelog.

Thank you to everyone who tested the previous release, and thank you to the folks who contributed patches!

      3 John Sirois
      1 Eric Arellano