Clean up warnings in Gradle build, polishing, etc.

spring-webmvc/src/test/java/org/springframework/web/servlet/view/RedirectViewTests.java

@@ -138,7 +138,6 @@ public class RedirectViewTests {
 	}
 
 	@Test
-	@SuppressWarnings("AssertEqualsBetweenInconvertibleTypes")
 	public void flashMap() throws Exception {
 		RedirectView rv = new RedirectView();
 		rv.setUrl("https://url.somewhere.com/path");

spring-webmvc/src/test/java/org/springframework/web/servlet/view/script/ScriptTemplateViewTests.java

@@ -304,7 +304,6 @@ public class ScriptTemplateViewTests {
 		assertThat(accessor.getPropertyValue("sharedEngine")).isEqualTo(true);
 	}
 
-	@SuppressWarnings("unchecked")
 	@Test  // gh-23258
 	public void engineSupplierWithNonSharedEngine() {
 		this.configurer.setEngineSupplier(() -> mock(InvocableScriptEngine.class));