Return 404 error for invalid URLs with double slashes.

Prior this change, it led to 500 error and long error stack traces in a log file.

Author: php-coder

src/main/java/ru/mystamps/web/support/spring/boot/ErrorPagesCustomizer.java

@@ -24,6 +24,8 @@
 import org.springframework.boot.web.servlet.ErrorPageRegistrar;
 import org.springframework.boot.web.servlet.ErrorPageRegistry;
 
+import org.springframework.security.web.firewall.RequestRejectedException;
+
 import ru.mystamps.web.Url;
 
 @Configuration
@@ -34,6 +36,7 @@ public void registerErrorPages(ErrorPageRegistry registry) {
 		registry.addErrorPages(
 			new ErrorPage(HttpStatus.FORBIDDEN, Url.FORBIDDEN_PAGE),
 			new ErrorPage(HttpStatus.NOT_FOUND, Url.NOT_FOUND_PAGE),
+			new ErrorPage(RequestRejectedException.class, Url.NOT_FOUND_PAGE),
 			new ErrorPage(Exception.class, Url.INTERNAL_ERROR_PAGE)
 		);
 	}