Implementing SSL support in astropy.vo.samp once supported by SAMP #6210

In #6201, I removed any HTTPS/SSL support in the astropy.vo.samp module, because it was broken with recent versions of Python, and SAMP isn't meant to work over HTTPS yet. However, @mbtaylor mentioned that it is possible that SAMP could end up supporting HTTPS for WebSAMP in future, so this is to remind us to keep track of this.

If HTTPS/SSL needs to be re-implemented, the code in #6201 can serve as a starting point, but we should at the same time make it so that all the SSL-related config is in a SSL config object rather than adding 5-6 keyword arguments each time (as was originally described in #2031).

In any case, no action is required until SAMP is meant to work over HTTPS.