Release Arrow 21.0.0 (next release after 20.0.0)

[alamb]

Follow on from #2172

• Planned Release Candidate: 2022-08-19 2022-08-18
• Planned Release and Publish to crates.io: 2022-08-22 2022-08-22

Items:

• Arrow 20.0.0 official release candidiate also has object_store crate code in it #2338
• Update create-tarball.sh and verify_release.sh script to skip object_store #2339
• Prepare for release 21.0.0 -- update version and CHANGELOG.md #2483
• Fix verify_release.sh script to run rustfmt in each crate individually #2506
• https://lists.apache.org/thread/g4nzgd57w6rbt7o4tkqpbdmrqg8tqrxz
• Release candidate approved
• Release to crates.io
• Draft update to DataFusion:

See full list here:
20.0.0...master

[alamb]

FWIW there is some work on release scripts needed for this issue: #2339

[alamb]

@andygrove @nevi-me @houqp -- I will be able to make an RC for the next release, but I will be somewhere without network access on the planned release date (2022-08-22). I wonder if one of you might be able to handle publishing this release?

It might be a good time to test that you have the appropriate cargo permissions setup

Alternately, I could move the schedule up a little (make the release candidate 2022-08-18 or 2022-08-17 )

Let me know if you have any preferences

[alamb]

Due to my own schedule (I am out next week with little internet access) I plan to make the release candidate Thursday Aug 18, 2022 so that I can release on Sunday Aug 21.

cc @tustvold @viirya

[alamb]

I plan to cut the release candidate in about 4 hours time, after running the changelog script one last time and merging #2483

[alamb]

RC is out for approval: https://lists.apache.org/thread/g4nzgd57w6rbt7o4tkqpbdmrqg8tqrxz

[alamb]

🤔 this looks like it was dropped when I was out last week 😢

I will get it out shortly

[alamb]

Approved and released: https://lists.apache.org/thread/h3x0b88vsxxyx2mmx9tcvcxdj9nsjv32