tests: make error handling the same as the main function (#15825)

vlib/net/http/request_test.v

@@ -174,7 +174,7 @@ fn test_multipart_form_body() {
 	assert parsed_form == form
 }
 
-fn test_parse_large_body() ? {
+fn test_parse_large_body() {
 	body := 'A'.repeat(101) // greater than max_bytes
 	req := 'GET / HTTP/1.1\r\nContent-Length: $body.len\r\n\r\n$body'
 	mut reader_ := reader(req)