Updates to the release scripts and associated documentation to be datafusion rather than arrow-datafusion

[alamb]

Part of #9691

Is your feature request related to a problem or challenge?

Now that DataFusion is its own top level apache project #9691 (comment) we need to update the various release scripts

Describe the solution you'd like

we need to update the release process scripts and documentation in

(link to reporter URL, mailing list name, and so on)

Describe alternatives you've considered

No response

Additional context

No response

[andygrove]

I am working on this and will have a PR up today.

Also, I created https://dist.apache.org/repos/dist/dev/datafusion and added a KEYS file (copied from Arrow and removed non DataFusion PMC members)

[andygrove]

I also created https://dist.apache.org/repos/dist/release/datafusion and added KEYS there as well