Make sure the generated values are available from a static context

This commit updates the tests of property values code generated to
invoke the generated code from a `static` context. This ensures that
the test fails if that's not the case.

This commit also updated LinkedHashMap handling that did suffer from
that problem.

Closes gh-34659

spring-beans/src/main/java/org/springframework/beans/factory/aot/BeanDefinitionPropertyValueCodeGeneratorDelegates.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2024 the original author or authors.
+ * Copyright 2002-2025 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -156,6 +156,8 @@ abstract class BeanDefinitionPropertyValueCodeGeneratorDelegates {
 						.builder(SuppressWarnings.class)
 						.addMember("value", "{\"rawtypes\", \"unchecked\"}")
 						.build());
+				method.addModifiers(javax.lang.model.element.Modifier.PRIVATE,
+						javax.lang.model.element.Modifier.STATIC);
 				method.returns(Map.class);
 				method.addStatement("$T map = new $T($L)", Map.class,
 						LinkedHashMap.class, map.size());