GH-43672: [C#] Schema should be optional on FlightInfo

[ndglover]

Rationale for this change

Schema is not required on a FlightInfo message and sometimes needs to be lazily evaluated on the server. This PR allows schema to be null on the FlightInfo since it will be picked up later when requests with those tickets are made.

What changes are included in this PR?

Are these changes tested?

Yes, added a test to confirm this behaviour

Are there any user-facing changes?

• GitHub Issue: [C#] Schema should be optional on FlightInfo #43672

[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 GitHub? https://github.com/apache/arrow/issues/new/choose

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

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

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or

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In the case of PARQUET issues on JIRA the title also supports:

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See also:

• Other pull requests
• Contribution Guidelines - Contributing Overview

[github-actions]

⚠️ GitHub issue #43672 has been automatically assigned in GitHub to PR creator.

[ndglover]

@CurtHagenlocher - any chance you could give this a quick review please?

@CurtHagenlocher - gentle nudge for a review please

[ndglover]

Hi all, sorry to @ so many people but I've had this PR outstanding for review for some time. Would anyone be able to give it a look over and merge if good. I'm keen to get a new release with this added and don't want to fork if possible,
@adamreeve
@assignUser
@jonkeane
@kou
@raulcd

[raulcd]

The change looks good to me but I don't have enough knowledge around the C# code base to know whether other changes would be required. I've triggered the CI jobs.

[CurtHagenlocher]

I'm sorry; I forgot about this PR :(.

[CurtHagenlocher]

Test failure looks unrelated

[ndglover]

Thanks @CurtHagenlocher @raulcd - much appreciated.

What's the process for making this into a release?

[raulcd]

This will be part of the 18.0.0. We do quarterly releases and the 18.0.0 release is schedule for next month.

[conbench-apache-arrow]

After merging your PR, Conbench analyzed the 4 benchmarking runs that have been run so far on merge-commit 6382c0a.

There were no benchmark performance regressions. 🎉

The full Conbench report has more details. It also includes information about 9 possible false positives for unstable benchmarks that are known to sometimes produce them.