commands: print security protocol support in debuginstall Over the past week I've had to instruct multiple people to run Python code to query the ssl module to see what TLS protocol support is present. I think it would be useful for `hg debuginstall` to print this info to make it easier to access and debug why Mercurial is complaining about using an insecure TLS 1.0 protocol. Ideally we'd also print the path to the CA cert bundle. But the APIs for querying that in sslutil can emit warnings, making it slightly more difficult to integrate into `hg debuginstall`. That work will have to wait for another day.