MB-48245: UseTLS for gocbcore Agents/DCPAgents only when able

+ Only in EE mode is TLSCertFile is available.
+ Set UseTLS:true only when TLSCertFile is available (it isn't in CE mode).

Change-Id: I4908aea853e96085720feded72b4e9559fdff499
Reviewed-on: http://review.couchbase.org/c/cbgt/+/160525
Well-Formed: Build Bot <build@couchbase.com>
Well-Formed: Restriction Checker
Reviewed-by: Abhinav Dangeti <abhinav@couchbase.com>
Tested-by: Abhinav Dangeti <abhinav@couchbase.com>

gocbcore_utils.go

@@ -127,7 +127,7 @@ func setupConfigParams(server string, options map[string]string) (
 	connStr = server
 	if connURL, err := url.Parse(server); err == nil {
 		if strings.HasPrefix(connURL.Scheme, "http") {
-			if options["authType"] == "cbauth" || len(TLSCertFile) > 0 {
+			if len(TLSCertFile) > 0 {
 				useTLS = true
 			}