[Go] update readme.go.md (#21219)

Author: Alancere

specification/elasticsan/resource-manager/readme.go.md

@@ -5,7 +5,7 @@ These settings apply only when `--go` is specified on the command line.
 ```yaml $(go) && $(track2)
 azure-arm: true
 license-header: MICROSOFT_MIT_NO_VERSION
-module-name: sdk/resourcemanager/elasticsans/armelasticsans
+module-name: sdk/resourcemanager/elasticsan/armelasticsan
 module: github.com/Azure/azure-sdk-for-go/$(module-name)
 output-folder: $(go-sdk-folder)/$(module-name)
 ```