gh-94172: Update docs for params removed in 3.12

[hugovk]

In the following modules, these parameters were removed (in #94173) after being deprecated in Python 3.6:

ftplib	imaplib	poplib	smptblib	http.client
keyfile	keyfile	keyfile	keyfile	key_file
certfile	certfile	certfile	certfile	cert_file
				check_hostname

This PR updates the documentation to remove the parameters and note their removal in 3.12.

Preview

• https://deploy-preview-100431--python-cpython-preview.netlify.app/library/ftplib.html
• https://deploy-preview-100431--python-cpython-preview.netlify.app/library/imaplib.html
• https://deploy-preview-100431--python-cpython-preview.netlify.app/library/poplib.html
• https://deploy-preview-100431--python-cpython-preview.netlify.app/library/smtplib.html
• https://deploy-preview-100431--python-cpython-preview.netlify.app/library/http.client.html

• Issue: Remove deprecated keyfile, certfile and check_hostname parameters, in favor of context #94172

[hauntsaninja]

Thanks for updating these! It looks like the remaining arguments were also made keyword-only.

[bedevere-bot]

When you're done making the requested changes, leave the comment: I have made the requested changes; please review again.

[hugovk]

I have made the requested changes; please review again.

---

Thanks, updated, and I'd also missed SMTP.starttls so done that one too.

I also fixed a bit of formatting whilst these files are being updated.

[bedevere-bot]

Thanks for making the requested changes!

@hauntsaninja: please review the changes made to this pull request.

[hauntsaninja]

Left some comments! Good catch on SMTP.starttls (I didn't check for any other errors of omission)

[hauntsaninja]

Can't leave a suggestion, but this one needs to be made keyword-only

[hugovk]

Updated in 25421ff

[hauntsaninja]

Btw, subject for a separate discussion, but I've never really liked the [param] syntax for optional parameters, since it's not close to any valid Python syntax. In some complicated signatures it may be necessary, but for the cases in this PR I feel like timeout=... or timeout=<default> or timeout=<unspecified> would be clearer.

[hugovk]

Thanks both for the reviews!

---

Btw, subject for a separate discussion, but I've never really liked the [param] syntax for optional parameters, since it's not close to any valid Python syntax. In some complicated signatures it may be necessary, but for the cases in this PR I feel like timeout=... or timeout=<default> or timeout=<unspecified> would be clearer.

Yeah, I guess [param] is following the Unix manual page format, and we don't have an unambiguous default compared to the others:

    def __init__(self, host, port=None, timeout=socket._GLOBAL_DEFAULT_TIMEOUT,
                 source_address=None, blocksize=8192):

[hauntsaninja]

Thank you!