test: Update JsonRpcExecutorHandler and test for timeout handling and…

… 408 status

- Implement 408 (Request Timeout) status code on timeout in JsonRpcExecutorHandler
- Update JsonRpcExecutorHandlerTest to verify 408 status and timer cancellation
- Improve error handling and test coverage for timeout scenarios
- Apply spotless formatting changes

This change ensures that a 408 status code is returned on timeout and
that timer cancellation is properly implemented and tested, improving
error handling for the JsonRpcExecutorHandler. Spotless formatting
has been applied to maintain code style consistency.

Issue: hyperledger#5589
PR: hyperledger#7469
Signed-off-by: Ade Lucas <ade.lucas@consensys.net>

ethereum/api/src/main/java/org/hyperledger/besu/ethereum/api/handlers/JsonRpcExecutorHandler.java

@@ -99,7 +99,8 @@ private static void cancelTimer(final RoutingContext ctx) {
     }
   }
 
-  private static void handleErrorAndEndResponse(final RoutingContext ctx, final Object id, final RpcErrorType errorType) {
+  private static void handleErrorAndEndResponse(
+      final RoutingContext ctx, final Object id, final RpcErrorType errorType) {
     if (!ctx.response().ended()) {
       handleJsonRpcError(ctx, id, errorType);
     }