Update packages to split utils, caching, rest functions to own packages

To help manage code, a split was established to extract different parts of the core package to their own package. This will help in the long term to keep the code more maintainable.

caching/src/main/java/org/eclipsefoundation/caching/config/LoadingCacheConfig.java

 /**
- * Copyright (c) 2023 Eclipse Foundation
+ * Copyright (c) 2023, 2024 Eclipse Foundation
  *
  * This program and the accompanying materials are made
  * available under the terms of the Eclipse Public License 2.0
@@ -9,7 +9,7 @@
  *
  * SPDX-License-Identifier: EPL-2.0
  */
-package org.eclipsefoundation.core.config;
+package org.eclipsefoundation.caching.config;
 
 import java.time.Duration;
 import java.util.Map;