http: Do not use a common name as https subject.

Otherwise, verification against IP-only CA certificate will fail, as
common name is sometimes used to contain a domain name (which is
deprecated in favour of alternative names, but still checked).

caucase/http.py

@@ -284,7 +284,7 @@ def getSSLContext(
         x509.CertificateSigningRequestBuilder(
           subject_name=x509.Name([
             x509.NameAttribute(
-              oid=x509.oid.NameOID.COMMON_NAME,
+              oid=x509.oid.NameOID.ORGANIZATIONAL_UNIT_NAME,
               value=hostname_dnsname,
             ),
           ]),