Remove channel binding requirement from clientcert=verify-full test.
This fails on older OpenSSL versions that lack channel binding
support. Since that feature is not essential to this test case,
just remove it, instead of complicating matters. Per buildfarm.
Jacob Champion
Discussion: https://postgr.es/m/
fa8dbbb58c20b1d1adf0082769f80d5466eaf485.camel@vmware.com