Configure index in @ParameterizedTest display names

This commit prepends "[{index}] " to all custom display names
configured via @ParameterizedTest.

This provides better diagnostics between the "technical names" reported
on the CI server vs. the "display names" reported within a developer's
IDE.

See gh-23451

spring-websocket/src/test/java/org/springframework/web/socket/AbstractWebSocketIntegrationTests.java

@@ -74,7 +74,7 @@ public abstract class AbstractWebSocketIntegrationTests {
 
 	@Retention(RetentionPolicy.RUNTIME)
 	@Target(ElementType.METHOD)
-	@ParameterizedTest(name = "server [{0}], client [{1}]")
+	@ParameterizedTest(name = "[{index}] server [{0}], client [{1}]")
 	@MethodSource("argumentsFactory")
 	protected @interface ParameterizedWebSocketTest {
 	}