[🚀 Feature]: Grid implement capability to set download directory

[titusfortner]

Feature and motivation

I'm breaking up #11443 to clarify the different things that need to be implemented.

Have node:
* Check if se:enableDownloads is set true
* Generate new UUID (can't be session ID, because grid needs to know the download location before the session ID is created)
* Create directory at $HOME/.cache/selenium/downloads/
* Add that directory to correct browser vendor namespaced preference requirements (see below)
* Somehow stores the location of that directory for future calls to the se/files endpoints
* Deletes directory when session ends

For Chrome/Edge this preferences are:

"download.prompt_for_download": false
"download.default_directory": downloadDirectory

For Firefox this is:

"browser.download.folderList": 2
"browser.download.dir": downloadDirectory

Usage example

This is back end support for bindings

[github-actions]

@titusfortner, thank you for creating this issue. We will troubleshoot it as soon as we can.

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