Change max regex length in SpEL expressions to 1000

This commit changes the max regex length in SpEL expressions from 1024
to 1000 in order to consistently use "round" numbers for recently
introduced limits.

See gh-30265

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 = 1024;
+	private static final int MAX_REGEX_LENGTH = 1000;
 
 	private final ConcurrentMap<String, Pattern> patternCache;
 

spring-expression/src/test/java/org/springframework/expression/spel/EvaluationTests.java

@@ -484,13 +484,13 @@ void matchesWithPatternAccessThreshold() {
 
 		@Test
 		void matchesWithPatternLengthThreshold() {
-			String pattern = "(%s|X)".formatted("1234".repeat(255));
-			assertThat(pattern).hasSize(1024);
+			String pattern = "^(%s|X)".formatted("12345".repeat(199));
+			assertThat(pattern).hasSize(1000);
 			Expression expr = parser.parseExpression("'X' matches '" + pattern + "'");
 			assertThat(expr.getValue(context, Boolean.class)).isTrue();
 
 			pattern += "?";
-			assertThat(pattern).hasSize(1025);
+			assertThat(pattern).hasSize(1001);
 			evaluateAndCheckError("'abc' matches '" + pattern + "'", Boolean.class, SpelMessage.MAX_REGEX_LENGTH_EXCEEDED);
 		}