No way to disable traceback colors when executing notebook

[dionhaefner]

Reproducer:

1. Jupyter notebook with a single cell that throws an exception:

{
 "cells": [
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "assert False"
   ]
  }
 ],
 "metadata": {
  "language_info": {
   "name": "python"
  }
 },
 "nbformat": 4,
 "nbformat_minor": 2
}

(foo.ipynb)

2. Run nbconvert --execute and pipe to a file:

$ jupyter nbconvert --to notebook --execute foo.ipynb > foo.txt 2>&1

3. foo.txt contains raw escape codes (ANSI terminal colors):

[NbConvertApp] Converting notebook foo.ipynb to notebook
<snip>
nbclient.exceptions.CellExecutionError: An error occurred while executing the following cell:
------------------
assert False
------------------


�[0;31m---------------------------------------------------------------------------�[0m
�[0;31mAssertionError�[0m                            Traceback (most recent call last)
Cell �[0;32mIn[1], line 1�[0m
�[0;32m----> 1�[0m �[38;5;28;01massert�[39;00m �[38;5;28;01mFalse�[39;00m

�[0;31mAssertionError�[0m: 

This makes our server logs unreadable and makes it harder for users to find out why notebook execution failed.

Is there any way to disable traceback coloring?