[gradle] Enabling up-to-date checks and gradle caching for openapigenerator tasks (#6716)

modules/openapi-generator-gradle-plugin/samples/local-spec/README.md

@@ -1,18 +1,18 @@
 # Local Spec Sample
 
-This example assumes you have Gradle 4.7+ installed. No gradle wrapper is provided in samples.
+This example assumes you have Gradle 5.6.4+ installed. No gradle wrapper is provided in samples.
 
-First, publish the openapi-generator-gradle-plugin locally via `./gradlew assemble install` in the module directory.
+First, publish the openapi-generator-gradle-plugin locally via `./gradlew assemble publishToMavenLocal` in the module directory.
 
 Then, run the following tasks in this example directory.
 
 ```bash
-gradle openApiGenerate
-gradle openApiMeta
-gradle openApiValidate
-gradle buildGoSdk
-gradle buildDotnetSdk
-gradle generateGoWithInvalidSpec
+gradle openApiGenerate              # expected outcome: BUILD SCCESSFUL
+gradle openApiMeta                  # expected outcome: BUILD SCCESSFUL
+gradle openApiValidate              # expected outcome: BUILD FAILED 
+gradle buildGoSdk                   # expected outcome: BUILD SCCESSFUL
+gradle buildDotnetSdk               # expected outcome: BUILD SCCESSFUL
+gradle generateGoWithInvalidSpec    # expected outcome: BUILD FAILED 
 ```
 
 The samples can be tested against other versions of the plugin using the `openApiGeneratorVersion` property. For example: