[BUG] - Use of MD5 algorithm in FIPs system

[jose-pr]

Are you using paramiko as a client or server?

Client

What feature(s) aren't working right?

SSH, SFTP, Keys/auth, known_hosts

What version(s) of paramiko are you using?

3.4

What version(s) of Python are you using?

3.11

What operating system and version are you using?

Rocky 9

If you're connecting as a client, which SSH server are you connecting to?

No response

If you're using paramiko as part of another tool, which tool/version?

No response

Expected/desired behavior

Being able to open a ssh connection.

Actual behavior

When using a systems with FIPS enabled md5 hash will fail.
In my case i couldn't even open a connection because of PKey when using key auth or when adding a new host. Due to its use in the
debug log

        client._log(
            DEBUG,
            "Adding {} host key for {}: {}".format(
                key.get_name(), hostname, hexlify(key.get_fingerprint())
            ),
        )

paramiko/paramiko/pkey.py

Line 344 in 51eb55d

return md5(self.asbytes()).digest()

How to reproduce

No response

Anything else?

Not use md5, not sure if sha1 would also be problematic with FIP. At least not depend on hashlib with depends on openssl which will fail.
Maybe use sha256 instead?