Convert sftp hook to use paramiko instead of pysftp

[pauldalewilliams]

This PR is a major change to the SFTP provider to remove the dependency on pysftp and use paramiko via the SSHHook instead. The provider was previously inconsistent in its use of pysftp vs the SSHHook. The SFTPHook used pysftp to actually create its connection and perform operations, but it inherited from SSHHook. The SFTPOperator did not use the SFTPHook or pysftp and instead used the SSHHook to create its connection and use the SFTP operations provided by paramiko. This PR rewrites the provider so the SFTPHook uses the SSHHook and paramiko (via SSHHook) and the SFTPOperator uses the SFTPHook. This enables support for all of the parameters supported by the SSHHook and creates consistency within the SFTP provider. There should be no breaking changes aside from the removal of previously deprecated parameters in the SFTPHook since pysftp used paramiko under the hood anyway.

A number of changes are contained in this PR:

• Minor change to the SSH provider to support ciphers as an optional extra parameter, which is used by the SFTPHook
• Deprecated parameters in the SFTP provider were completely removed since this is a major change to the provider (seemed appropriate, but let me know if that should not have been done yet)
• Any functionality provided by pysftp that was used by the SFTPHook has been incorporated directly into the provider
• SFTPHook supports passing an SSHHook to continue supporting that option in the SFTPOperator; however, this is marked as deprecated and should be removed in a future major version. SFTPOperator warns users to pass an SFTPHook instead now.
• _make_intermediate_dirs was removed from SFTPOperator since the create_directory method on SFTPHook supports creating parent directories of subdirectories (functionally equivalent)
• typing was added to SFTPOperator

Tests have been written to achieve 100% code coverage and all tests are passing. Previously existing tests were only modified where required to ensure backward compatibility with the provider's original functionality. Please double-check my tests though as I'm not confident in my test writing abilities yet. Docs have been updated as well.

I will note there was brief discussion with @malthe on Slack to consider using parallel-ssh instead but I opted to hold off on that for now. That could be a good future update since some have reported issues with paramiko (for example, #16286).

[pauldalewilliams]

One other note I forgot to include: the default for no_host_key_check used to be true for SFTPHook but it will now default to false since that is the default for SSHHook. That's not a breaking change but those relying on it to default to true will need to explicitly add it to the extra parameters on the connection.

The primary motivation for doing this was to ensure that the SFTP connections can support all of the parameters supported by SSHHook. Because pysftp did not support passing all those parameters to paramiko I figured this was the best way to get that consistency.

[github-actions]

The PR most likely needs to run full matrix of tests because it modifies parts of the core of Airflow. However, committers might decide to merge it quickly and take the risk. If they don't merge it quickly - please rebase it to the latest main at your convenience, or amend the last commit of the PR, and push it with --force-with-lease.

[potiuk]

Nice an detailed errors.