[VOTE] Release Apache Traffic Control RELEASE-6.0.0-RC4

[Zach Hoffman]

I've prepared a release for 6.0.0-RC4. Changes since RELEASE-5.1.2:

        
https://github.com/apache/trafficcontrol/compare/RELEASE-5.1.2...RELEASE-6.0.0-RC4
        
https://github.com/apache/trafficcontrol/blob/RELEASE-6.0.0-RC4/CHANGELOG.md

The artifacts are available for download at:

        https://dist.apache.org/repos/dist/dev/trafficcontrol/6.0.0/RC4/

BLAKE2 checksum:
94e462c1d751edc60f398dc7c588603190cc830e029fbb39acdee74d291a31ffb7d1bdc74fad4678f146c463f43b82537c0706183149c7b85b7564f98e093a94
  apache-trafficcontrol-6.0.0.tar.gz

SHA512 checksum:
94da739c6af1cbb307d192e24d346de13cab2a139e5233fafdaa5308729dece748f15beab6a8ab0b7caa160f3c9116ecb986da101ace6aaaf65738036a00ea89
  apache-trafficcontrol-6.0.0.tar.gz

This corresponds to git refs:

        Hash: 5a2eea21a3175ad76839d54cacbd0386c09966f4
        Tag: RELEASE-6.0.0-RC4

Which can be verified with the following command:

        $ git tag -v RELEASE-6.0.0-RC4

All code signing keys are available here:

        https://dist.apache.org/repos/dist/release/trafficcontrol/KEYS

Make sure you refresh from a key server to get all relevant signatures.

The vote is open until 22:00 UTC on Monday, October 4 and passes if a majority 
of at least 3 +1 PMC votes are cast.
        [ ] +1 approve
        [ ] +0 no opinion
        [ ] -1 disapprove (and reason why)

-Zach