Do not include escape codes when logging to file

We shouldn't be printing terminal escape codes when logging to file.

The log files currently look like this:

[2m2024-02-22T18:09:58Z[0m [32m INFO[0m [2marti[0m[2m:[0m Starting Arti 1.1.13 in SOCKS proxy mode on localhost port 9150 ...
[2m2024-02-22T18:09:58Z[0m [34mDEBUG[0m [2marti::process[0m[2m:[0m Increased process file limit to 16384

I routinely sed -i "s,\x1B\[[0-9;]*[a-zA-Z],,g" logs from bug reports, shadow etc. in order to make them readable.