Increase max regex length in SpEL expressions

This commit increases the max regex length in SpEL expressions from 256
to 1024 in order to support use cases where a regex may be rather long
without necessarily increasing the complexity of the regex.

Closes gh-30298

spring-expression/src/main/java/org/springframework/expression/spel/ast/OperatorMatches.java

@@ -47,7 +47,7 @@ public class OperatorMatches extends Operator {
 	 * Maximum number of characters permitted in a regular expression.
 	 * @since 5.2.23
 	 */
-	private static final int MAX_REGEX_LENGTH = 256;
+	private static final int MAX_REGEX_LENGTH = 1024;
 
 	private final ConcurrentMap<String, Pattern> patternCache;