SEBA-902 single-olt tests;
Pin protoc-gen-go to 1.3.2 to resolve compatibility issue;
Run go mod tidy / go mod vendor on importer;
Add Go Module support to demotest

Change-Id: Ifde824fc9a6317b0adc1e12bea54ee1f9b788906
diff --git a/vendor/gopkg.in/jcmturner/gokrb5.v7/client/passwd.go b/vendor/gopkg.in/jcmturner/gokrb5.v7/client/passwd.go
index e6d4180..da838ed 100644
--- a/vendor/gopkg.in/jcmturner/gokrb5.v7/client/passwd.go
+++ b/vendor/gopkg.in/jcmturner/gokrb5.v7/client/passwd.go
@@ -44,7 +44,7 @@
 		return false, err
 	}
 	if r.ResultCode != KRB5_KPASSWD_SUCCESS {
-		return false, fmt.Errorf("error response from kdamin: %s", r.Result)
+		return false, fmt.Errorf("error response from kadmin: code: %d; result: %s; krberror: %v", r.ResultCode, r.Result, r.KRBError)
 	}
 	cl.Credentials.WithPassword(newPasswd)
 	return true, nil