Add Chinese translation of "http_proxies"

[alaahong]

Description

Add Chinese translation of "http_proxies"

• webdriver/http_proxies.zh-cn.md

Motivation and Context

Types of changes

• Change to the site (I am attaching a screenshot showing the before and after)
• Code example added (and I also added the example to all translated languages)
• Improved translation
• Added new translation (and I also added a notice to each document missing translation)

Checklist

• I have read the contributing document.
• I have used hugo to render the site/docs locally and I am sure it works.

[diemol]

Thank you @alaahong!