Use latest available Gradle version for Paketo system tests

This ensures that the tests will run with the latest Java versions.

See spring-projectsgh-37507

Author: scottfrederick

spring-boot-project/spring-boot-tools/spring-boot-gradle-test-support/src/main/java/org/springframework/boot/testsupport/gradle/testkit/GradleVersions.java

@@ -44,6 +44,11 @@ public static String minimumCompatible() {
 		return allCompatible().get(0);
 	}
 
+	public static String maximumCompatible() {
+		List<String> versions = allCompatible();
+		return versions.get(versions.size() - 1);
+	}
+
 	private static boolean isJavaVersion(JavaVersion version) {
 		return JavaVersion.current().isCompatibleWith(version);
 	}

spring-boot-system-tests/spring-boot-image-tests/src/systemTest/java/org/springframework/boot/image/paketo/PaketoBuilderTests.java

@@ -46,6 +46,7 @@
 import org.springframework.boot.image.junit.GradleBuildInjectionExtension;
 import org.springframework.boot.testsupport.gradle.testkit.GradleBuild;
 import org.springframework.boot.testsupport.gradle.testkit.GradleBuildExtension;
+import org.springframework.boot.testsupport.gradle.testkit.GradleVersions;
 import org.springframework.util.StringUtils;
 
 import static org.assertj.core.api.Assertions.assertThat;
@@ -72,6 +73,7 @@ void configureGradleBuild() {
 		this.gradleBuild.scriptPropertyFrom(new File("../../gradle.properties"), "nativeBuildToolsVersion");
 		this.gradleBuild.expectDeprecationMessages("BPL_SPRING_CLOUD_BINDINGS_ENABLED.*true.*Deprecated");
 		this.gradleBuild.expectDeprecationMessages("BOM table is deprecated");
+		this.gradleBuild.gradleVersion(GradleVersions.maximumCompatible());
 	}
 
 	@Test
@@ -298,6 +300,9 @@ void plainWarApp() throws Exception {
 	@EnabledForJreRange(max = JRE.JAVA_17)
 	void nativeApp() throws Exception {
 		this.gradleBuild.expectDeprecationMessages("uses or overrides a deprecated API");
+		// these deprecations are transitive from the Native Build Tools Gradle plugin
+		this.gradleBuild.expectDeprecationMessages("has been deprecated. This is scheduled to be removed in Gradle 9.0");
+		this.gradleBuild.expectDeprecationMessages("upgrading_version_8.html#deprecated_access_to_convention");
 		writeMainClass();
 		String imageName = "paketo-integration/" + this.gradleBuild.getProjectDir().getName();
 		ImageReference imageReference = ImageReference.of(ImageName.of(imageName));

spring-boot-system-tests/spring-boot-image-tests/src/systemTest/resources/org/springframework/boot/image/paketo/PaketoBuilderTests-bootDistZipJarApp.gradle

@@ -39,5 +39,5 @@ application {
 bootBuildImage {
 	builder = "paketobuildpacks/builder-jammy-base:latest"
 	archiveFile = bootDistZip.archiveFile
-	environment = ['BP_JVM_VERSION': project.targetCompatibility.getMajorVersion()]
+	environment = ['BP_JVM_VERSION': java.targetCompatibility.getMajorVersion()]
 }

spring-boot-system-tests/spring-boot-image-tests/src/systemTest/resources/org/springframework/boot/image/paketo/PaketoBuilderTests-plainDistZipJarApp.gradle

@@ -39,5 +39,5 @@ application {
 bootBuildImage {
 	builder = "paketobuildpacks/builder-jammy-base:latest"
 	archiveFile = distZip.archiveFile
-	environment = ['BP_JVM_VERSION': project.targetCompatibility.getMajorVersion()]
+	environment = ['BP_JVM_VERSION': java.targetCompatibility.getMajorVersion()]
 }

spring-boot-system-tests/spring-boot-image-tests/src/systemTest/resources/org/springframework/boot/image/paketo/PaketoBuilderTests-plainWarApp.gradle

@@ -32,5 +32,5 @@ war {
 bootBuildImage {
 	builder = "paketobuildpacks/builder-jammy-base:latest"
 	archiveFile = war.archiveFile
-	environment = ['BP_JVM_VERSION': project.targetCompatibility.getMajorVersion(), 'BP_TOMCAT_VERSION': '10.*']
+	environment = ['BP_JVM_VERSION': java.targetCompatibility.getMajorVersion(), 'BP_TOMCAT_VERSION': '10.*']
 }