chore(proto): permit AlterConfigsRequest V1

This is identical in format to V0, but just influences the broker's response behaviour

admin.go

@@ -716,6 +716,9 @@ func (ca *clusterAdmin) AlterConfig(resourceType ConfigResourceType, name string
 		Resources:    resources,
 		ValidateOnly: validateOnly,
 	}
+	if ca.conf.Version.IsAtLeast(V2_0_0_0) {
+		request.Version = 1
+	}
 
 	var (
 		b   *Broker

alter_configs_request.go

@@ -123,9 +123,16 @@ func (a *AlterConfigsRequest) headerVersion() int16 {
 }
 
 func (a *AlterConfigsRequest) isValidVersion() bool {
-	return a.Version == 0
+	return a.Version >= 0 && a.Version <= 1
 }
 
 func (a *AlterConfigsRequest) requiredVersion() KafkaVersion {
-	return V0_11_0_0
+	switch a.Version {
+	case 1:
+		return V2_0_0_0
+	case 0:
+		return V0_11_0_0
+	default:
+		return V2_0_0_0
+	}
 }

alter_configs_response.go

@@ -113,11 +113,18 @@ func (a *AlterConfigsResponse) headerVersion() int16 {
 }
 
 func (a *AlterConfigsResponse) isValidVersion() bool {
-	return a.Version == 0
+	return a.Version >= 0 && a.Version <= 1
 }
 
 func (a *AlterConfigsResponse) requiredVersion() KafkaVersion {
-	return V0_11_0_0
+	switch a.Version {
+	case 1:
+		return V2_0_0_0
+	case 0:
+		return V0_11_0_0
+	default:
+		return V2_0_0_0
+	}
 }
 
 func (r *AlterConfigsResponse) throttleTime() time.Duration {