Polish MimeTypeUtils LRU cache

This commit improves the cache implementation by skipping the ordering
of most recently used cached keys when the cache is at least half empty.

See gh-23211

Author: bclozel

spring-core/src/main/java/org/springframework/util/MimeTypeUtils.java

@@ -433,7 +433,13 @@ public ConcurrentLruCache(int maxSize, Function<K, V> generator) {
 		public V get(K key) {
 			this.lock.readLock().lock();
 			try {
-				if (this.queue.remove(key)) {
+				if (this.queue.size() < this.maxSize / 2) {
+					V cached = this.cache.get(key);
+					if (cached != null) {
+						return cached;
+					}
+				}
+				else if (this.queue.remove(key)) {
 					this.queue.add(key);
 					return this.cache.get(key);
 				}