Adjust test after fixing the C/C.
On Windows, use --host=127.0.0.2 to fake "insecure" transport
with TCP connection for test purposes. 127.0.0.2 is loopback address,
that can be used instead of usual 127.0.0.1
Unfortunately, this technique does not work on all *nixes the same,
notably neither on BSDs nor Solaris. Thus default --host=localhost
remains "insecure" transport,when TCP is used. but it is not that critical,
the "self-signed" is not nearly as annoying on *nixes as it is on Windows.
if the client enabled --ssl-verify-server-cert, then
the server certificate is verified as follows:
* if --ssl-ca or --ssl-capath were specified, the cert must have
a proper signature by the specified CA (or CA in the path)
and the cert's hostname must match the server's hostname.
If the cert isn't signed or a hostname is wrong - the
connection is aborted.
* if MARIADB_OPT_TLS_PEER_FP was used and the fingerprint matches,
the connection is allowed, if it doesn't match - aborted.
* If the connection uses unix socket or named pipes - it's allowed.
(consistent with server's --require-secure-transport behavior)
otherwise the cert is still in doubt, we don't know if we can trust
it or there's an active MitM in progress.
* If the user has provided no password or the server requested an
authentication plugin that sends the password in cleartext -
the connection is aborted.
* Perform the authentication. If the server accepts the password,
it'll send SHA2(scramble || password hash || cert fingerprint)
with the OK packet.
* Verify the SHA2 digest, if it matches - the connection is allowed,
otherwise it's aborted.
Test fixes:
Since fix for CONC-603 (wrong error handling in TLS read/write) in case
of a read/write error client doesn't return always error 2013 (server
has gone away), so in addition we need to check for error 2026
(TLS/SSL error) and 5014 (write error).