Update tests with coverage docs with Gradle examples

docs/src/main/asciidoc/tests-with-coverage.adoc

@@ -173,6 +173,13 @@ Now we need to add Jacoco to our project. To do this we need to add the followin
 </dependency>
 ----
 
+If you are using Gradle, add this to your `build.gradle`:
+
+[source,gradle]
+----
+testImplementation 'io.quarkus:quarkus-jacoco'
+----
+
 This Quarkus extension takes care of everything that would usually be done via the Jacoco maven plugin, so no additional
 config is required.
 
@@ -239,6 +246,27 @@ In addition to including the `quarkus-jacoco` extension in your pom you will nee
 WARNING: This config will only work if at least one `@QuarkusTest` is being run. If you are not using `@QuarkusTest` then
 you can simply use the Jacoco plugin in the standard manner with no additional config.
 
+If you are using Gradle, add this to your `build.gradle`:
+
+[source,gradle,subs=attributes+]
+----
+plugins {
+    id 'jacoco' <1>
+}
+
+test {
+    finalizedBy jacocoTestReport
+    jacoco {
+        excludeClassLoaders = ["*QuarkusClassLoader"] <2>
+        destinationFile = layout.buildDirectory.file("jacoco-quarkus.exec").get().asFile <2>
+    }
+    jacocoTestReport.enabled = false <3>
+}
+----
+<1> Add the `jacoco` gradle plugin
+<2> This config tells it to ignore `@QuarkusTest` related classes, as they are loaded by `QuarkusClassLoader`
+<3> Set this config to `false` if you are also using the `quarkus-jacoco` extension and have at least one `@QuarkusTest`.  The default `jacocoTestReport` task can be skipped since `quarkus-jacoco` will generate the combined report of regular unit tests and `@QuarkusTest` classes since the execution data is recorded in the same file.
+
 === Coverage for Integration Tests
 
 To get code coverage data from integration tests, the following need to be requirements need to be met:
@@ -375,6 +403,49 @@ You can set thresholds for code coverage using the Jacoco Maven plugin. Note the
 </build>
 ----
 
+If you are using Gradle, add this to your `build.gradle`:
+
+[source, gradle]
+----
+jacocoTestCoverageVerification {
+    executionData.setFrom("$project.buildDir/jacoco-quarkus.exec")
+    violationRules {
+        rule {
+            limit {
+                counter = 'INSTRUCTION'
+                value = 'COVEREDRATIO'
+                minimum = 0.80
+            }
+            limit {
+                counter = 'BRANCH'
+                value = 'COVEREDRATIO'
+                minimum = 0.72
+            }
+        }
+    }
+}
+check.dependsOn jacocoTestCoverageVerification
+----
+
+Excluding classes from the verification task can be configured as following: 
+
+[source,gradle]
+----
+jacocoTestCoverageVerification {
+    afterEvaluate { <1>
+        classDirectories.setFrom(files(classDirectories.files.collect { <2>
+            fileTree(dir: it, exclude: [
+                    "org/example/package/**/*" <3>
+            ])
+        }))
+    }
+}
+----
+<1> `classDirectories` needs to be read after evaluation phase in Gradle
+<2> Currently, there is a bug in Gradle JaCoCo which requires the `excludes` to be specified in this manner - https://github.com/gradle/gradle/issues/14760.  Once this issue is fixed, excludes
+<3> Exclude all classes in `org/example/package` package
+
+
 == Conclusion
 
 You now have all the information you need to study the coverage of your tests!