fix: usr: Fix a zone transfer over TLS (XoT) issue when using the opportunistic TLS...

The :iscman:`named` process, running as secondary DNS server,
configured to transfer a zone from a primary server using an
encrypted XoT transport in opportunistic TLS mode (i.e. without
peer certificate/hostname validation) could terminate unexpectedly
when the TLS ALPN negotiation with primary server was unsuccessful.
This has been fixed.

Closes #5957

Merge branch '5957-xot-xfrin_connect_done-bug-fix' into 'main'

See merge request isc-projects/bind9!12081