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/github.com/Shopify/sarama/produce_set.go b/vendor/github.com/Shopify/sarama/produce_set.go
index b684aa4..36c43c6 100644
--- a/vendor/github.com/Shopify/sarama/produce_set.go
+++ b/vendor/github.com/Shopify/sarama/produce_set.go
@@ -129,6 +129,10 @@
 		req.Version = 3
 	}
 
+	if ps.parent.conf.Producer.Compression == CompressionZSTD && ps.parent.conf.Version.IsAtLeast(V2_1_0_0) {
+		req.Version = 7
+	}
+
 	for topic, partitionSets := range ps.msgs {
 		for partition, set := range partitionSets {
 			if req.Version >= 3 {