add support to configure anonymous in s3 clients

[gweaverbiodev]

Rationale for this change

Currently, it is not possible to configure anonymous in the underlying s3fs client (False by default).

Resolves #2126

Are these changes tested?

Yes, unit tests added to confirm the setting is used when the property is set.

Are there any user-facing changes?

Yes, users can now set the property s3.anonymous to True to enable. If not set, the behavior will be the same as it currently is.

[Fokko]

Thanks @gmweaver for adding this 🙌

Probably we want to add this to the docs as well: https://github.com/apache/iceberg-python/blob/main/mkdocs/docs/configuration.md#s3

Do you know if there is a PyArrow equialent? If so, it would be nice to add that option as well.

[gweaverbiodev]

Do you know if there is a PyArrow equialent? If so, it would be nice to add that option as well.

pyarrow has a similar config updated the PR to include.

[Fokko]

@gmweaver Thanks for being on top of this, could you run make lint to fix the style issues?

[gweaverbiodev]

@Fokko sorry missed the make lint in the docs, updated

[kevinjqliu]

LGTM! Thanks for adding this. Heres the docs for both fsspec and pyarrow

https://s3fs.readthedocs.io/en/latest/api.html
https://arrow.apache.org/docs/python/generated/pyarrow.fs.S3FileSystem.html

[kevinjqliu]

Thanks for the PR @gmweaver and thank you @Fokko for the review!