GH-34956: [Docs][Python] Add to docs the usage of the FixedShapeTensorType

[AlenkaF]

Rationale for this change

This PR adds examples of the use of FixedShapeTensorTypeto the PyArrow user guide. Should be reviewed and merged after #34883 is done.

• Closes: [Docs][Python] Add to docs the usage of the FixedShapeTensorType #34956

[github-actions]

• Closes: [Docs][Python] Add to docs the usage of the FixedShapeTensorType #34956

[AlenkaF]

[rok]

Just two nits.

[rok]

LGTM!

[AlenkaF]

I am currently adding some more text. Will probably have extra content ready tomorrow morning!

[jorisvandenbossche]

Looks good! Some small comments.

I understand that we initially added this to extending_types.rst (when it was an example of implementing it). But now this is actually part of pyarrow, I am wondering if we would want to move it to a different location in our docs.
Currently, other data types are mentioned at https://arrow.apache.org/docs/dev/python/data.html, but that's already a long page about a lot of things, so also wouldn't just add it there. Maybe for now we can keep it here, and can think about reorganizing it later.

[AlenkaF]

I understand that we initially added this to extending_types.rst (when it was an example of implementing it). But now this is actually part of pyarrow, I am wondering if we would want to move it to a different location in our docs.
Currently, other data types are mentioned at https://arrow.apache.org/docs/dev/python/data.html, but that's already a long page about a lot of things, so also wouldn't just add it there. Maybe for now we can keep it here, and can think about reorganizing it later.

I will open an issue for this as I agree it should be reorganised (and I just remembered we have talked about this before, sorry).

Otherwise I have included the changes with the last two commits.

[AlenkaF]

Thank you Joris and Rok for reviews!
The issue to rearrange Data Types user guide section can be found here: #35064

[ursabot]

Benchmark runs are scheduled for baseline = 07642fd and contender = b8427d3. b8427d3 is a master commit associated with this PR. Results will be available as each benchmark for each run completes.
Conbench compare runs links:
[Finished ⬇️0.0% ⬆️0.0%] ec2-t3-xlarge-us-east-2
[Failed] test-mac-arm
[Finished ⬇️4.59% ⬆️1.79%] ursa-i9-9960x
[Finished ⬇️0.77% ⬆️0.0%] ursa-thinkcentre-m75q
Buildkite builds:
[Finished] b8427d39 ec2-t3-xlarge-us-east-2
[Failed] b8427d39 test-mac-arm
[Finished] b8427d39 ursa-i9-9960x
[Finished] b8427d39 ursa-thinkcentre-m75q
[Finished] 07642fd5 ec2-t3-xlarge-us-east-2
[Failed] 07642fd5 test-mac-arm
[Finished] 07642fd5 ursa-i9-9960x
[Finished] 07642fd5 ursa-thinkcentre-m75q
Supported benchmarks:
ec2-t3-xlarge-us-east-2: Supported benchmark langs: Python, R. Runs only benchmarks with cloud = True
test-mac-arm: Supported benchmark langs: C++, Python, R
ursa-i9-9960x: Supported benchmark langs: Python, R, JavaScript
ursa-thinkcentre-m75q: Supported benchmark langs: C++, Java

[ursabot]

['Python', 'R'] benchmarks have high level of regressions.
ursa-i9-9960x