Missing Extended Key Usage

## Environment

* Operating system (including version): MacOS 13.1
* mkcert version (from `mkcert -version`): v1.4.4
* Server (where the certificate is loaded): Locally
* Client (e.g. browser, CLI tool, or script): Proxyman

## What you did

* `mkcert -install`
* added root ca to *Proxyman*
* launched *Proxyman*

## What went wrong

Basically nothing, everything still works fine, but Proxyman always throws an error in my face at launch

It turns out that EKU is required for MacOS ≥10.15 [link to apple article](https://support.apple.com/en-us/HT210176)