Merge pull request spring-projects#17411 from dreis2211

* spring-projectsgh-17411:
  Polish "Polish GradleCompatibilityExtension's javadoc"
  Polish GradleCompatibilityExtension's javadoc

Closes spring-projectsgh-17411

Author: wilkinsona

spring-boot-project/spring-boot-tools/spring-boot-gradle-plugin/src/test/java/org/springframework/boot/gradle/junit/GradleCompatibilityExtension.java

@@ -20,6 +20,7 @@
 import java.util.List;
 import java.util.stream.Stream;
 
+import org.junit.jupiter.api.TestTemplate;
 import org.junit.jupiter.api.extension.Extension;
 import org.junit.jupiter.api.extension.ExtensionContext;
 import org.junit.jupiter.api.extension.TestTemplateInvocationContext;
@@ -30,7 +31,7 @@
 
 /**
  * {@link Extension} that runs {@link TestTemplate templated tests} against multiple
- * versions of Gradle. Test classes using the extension must have non-private and
+ * versions of Gradle. Test classes using the extension must have a non-private and
  * non-final {@link GradleBuild} field named {@code gradleBuild}.
  *
  * @author Andy Wilkinson