[Doc][Python] Better document the new pa.fs.HadoopFileSystem

[asfimport]

In order to deprecate the "legacy" pa.hdfs.HadoopFileSystem and pa.hdfs.connect(), we should ensure that the documentation for the new filesystem interface is fully up to date:

• The docstring of pyarrow.fs.HadoopFileSystem misses some keywords (that are included in the docstring of pa.hdfs.HaddopFileSystem)
• The user guide about the legacy one (https://arrow.apache.org/docs/python/filesystems_deprecated.html) contains more content, which should be added to the new user guide page as well (if still correct for the new filesystem)

Reporter: Joris Van den Bossche / @jorisvandenbossche
Assignee: Antoine Pitrou / @pitrou

PRs and other links:

• GitHub Pull Request #10867

_{Note: This issue was originally created as ARROW-9719. Please see the migration documentation for further details.}

[asfimport]

Antoine Pitrou / @pitrou:
The new filesystem section (https://arrow.apache.org/docs/python/filesystems.html#hadoop-file-system-hdfs) seems on parity with the old one now, can we close?

cc @amol-

[asfimport]

Joris Van den Bossche / @jorisvandenbossche:
I think the user guide has indeed been updated. Looking at the docstring, I think the content for user and extra_conf params can still be copied from pa.hdfs.connect to the new implementation.

[asfimport]

Antoine Pitrou / @pitrou:
Issue resolved by pull request 10867
#10867