Add support for downloading flights from alternate endpoints

[avantgardnerio]

• Add support for downloading flights from alternate EPs
  • arrow-ballista uses multiple executors to run a query in parallel, and this PR allows them each to serve their result
• Fix NPE when there are no extraParams
• Exclude more packages from Maven shade so developers can attach a debugger when integration testing shaded jar
  • e.g. when testing from one's favorite SQL IDE (DataGrip, SQLCommander, etc)
• Fix dep.protobuf.version build error
• Bump to v9 to match main repo

@jduo @jayhomn-bitquill @andygrove

See rafael-telles#42 for more detail.

Filing in response to apache#13900 (comment)

@lidavidm is this the correct place to PR to?

[github-actions]

Thanks for opening a pull request!

If this is not a minor PR. Could you open an issue for this pull request on JIRA? https://issues.apache.org/jira/browse/ARROW

Opening JIRAs ahead of time contributes to the Openness of the Apache Arrow project.

Then could you also rename pull request title in the following format?

ARROW-${JIRA_ID}: [${COMPONENT}] ${SUMMARY}

or

MINOR: [${COMPONENT}] ${SUMMARY}

See also:

• Other pull requests
• Contribution Guidelines - How to contribute patches

[lidavidm]

Hmm, I'm hoping we can get in the 'base' PR, then review these additions (which are very much welcomed). Also because I think we're supposed to keep discussion on Apache-maintained sites

[lidavidm]

Mostly because the base PR is so large, it's hard to keep it and all the changes in mind

[avantgardnerio]

Will re-open as a PR against the apache/arrow repo.