Significant latency increases when using betterproto 2.0.0b7 compared to 2.0.0b6

### Summary

Latency increases when using the newest version 2.0.0b7

### Reproduction Steps

This happened in a library we were using: https://github.com/cetanu/envoy_data_plane When we upgraded to betterproto 2.0.0b7 we saw a significant spike in the latency of our project. When we pinned the version to 2.0.0b6, the latency returned to normal. Do you have any ideas what might cause this issue?

### Expected Results

No latency changes

### Actual Results

Latency spiked causing increased timeouts within our project

### System Information

protoc --version; python --version; pip show betterproto
/bin/sh: 1: protoc: not found
Python 3.12.4
Name: betterproto
Version: 2.0.0b6
Summary: A better Protobuf / gRPC generator & library
Home-page: https://github.com/danielgtaylor/python-betterproto
Author: Daniel G. Taylor
Author-email: danielgtaylor@gmail.com
License: MIT
Location: /usr/local/lib/python3.12/site-packages
Requires: grpclib, python-dateutil
Required-by: envoy_data_plane

### Checklist

- [X] I have searched the issues for duplicates.
- [X] I have shown the entire traceback, if possible.
- [X] I have verified this issue occurs on the latest prelease of betterproto which can be installed using `pip install -U --pre betterproto`, if possible.

Reproduce the latency difference in the linked envoy_data_plane project, comparing betterproto 2.0.0b6 and 2.0.0b7 under Python 3.12.4. Profile the affected request path and identify the regression; done means a focused explanation and regression fix with a test or benchmark showing latency returns to baseline.

Scritto dal modello di indicizzazione a partire dal testo della issue.