Merge branch '3.0.x' into 3.1.x

Closes gh-37183

spring-boot-project/spring-boot-tools/spring-boot-buildpack-platform/src/test/java/org/springframework/boot/buildpack/platform/docker/type/ImageReferenceTests.java

@@ -180,6 +180,14 @@ class ImageReferenceTests {
 			.withMessageContaining("Unable to parse image reference");
 	}
 
+	@Test
+	void ofWhenContainsUpperCaseThrowsException() {
+		assertThatIllegalArgumentException()
+			.isThrownBy(() -> ImageReference
+				.of("europe-west1-docker.pkg.dev/aaaaaa-bbbbb-123456/docker-registry/bootBuildImage:0.0.1"))
+			.withMessageContaining("Unable to parse image reference");
+	}
+
 	@Test
 	void forJarFile() {
 		assertForJarFile("spring-boot.2.0.0.BUILD-SNAPSHOT.jar", "library/spring-boot", "2.0.0.BUILD-SNAPSHOT");