tls: CURLINFO_TLS_SSL_PTR testing

tls: CURLINFO_TLS_SSL_PTR testing

Add tests of CURLINFO_TLS_SSL_PTR and its returned value in test client
'hx-download'. Use obtained pointer to look up the negotiated TLS
version.

Update manpage of CURLINFO_TLS_SSL_PTR to also describe the behaviour of
wolfSSL similar to OpenSSL. Fix the wolfSSl implementation for TCP to
behave like that. Update the QUIC queries.

Fix rustls `get_internals()` to return the rustls_connection* and not
the address of the pointer.

Assisted-by: Viktor Szakats
Closes #18066