Use latest Spring Boot version when testing htmx

Author: mhalbritter

start-site/src/test/java/io/spring/start/site/extension/dependency/htmx/HtmxBuildCustomizerTests.java

@@ -31,7 +31,7 @@
  */
 class HtmxBuildCustomizerTests extends AbstractExtensionTests {
 
-	private static final SupportedBootVersion BOOT_VERSION = SupportedBootVersion.V3_4;
+	private static final SupportedBootVersion BOOT_VERSION = SupportedBootVersion.latest();
 
 	private final Dependency htmx = Dependency.withId("htmx", "io.github.wimdeblauwe", "htmx-spring-boot");