Merge branch '2.3.x'

Closes gh-22293

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

@@ -45,10 +45,10 @@ public final class GradleCompatibilityExtension implements TestTemplateInvocatio
 		JavaVersion javaVersion = JavaVersion.current();
 		if (javaVersion.isCompatibleWith(JavaVersion.VERSION_14)
 				|| javaVersion.isCompatibleWith(JavaVersion.VERSION_13)) {
-			GRADLE_VERSIONS = Arrays.asList("6.3", "default");
+			GRADLE_VERSIONS = Arrays.asList("6.3", "default", "6.5.1");
 		}
 		else {
-			GRADLE_VERSIONS = Arrays.asList("5.6.4", "6.3", "default");
+			GRADLE_VERSIONS = Arrays.asList("5.6.4", "6.3", "default", "6.5.1");
 		}
 	}