core: added capability to pass cookies as CLI parameter

[RynatSibahatau]

Summary

This feature adds the capability to pass cookies as a CLI parameter.

The current proposed approach to use "--extra-headers" parameter for setting cookies has a drawback for a wide range of enterprise applications that operates with the cookies (ex. authentication, localization, etc.).
Any Set-Cookie response from backend overwrites the Cookie header from extra-headers.
It introduces extra complexity of using lighthouse on CI in pure CLI mode (i.e without Puppeteer).
The fix intended to remove this complexity.

• lighthouse http://localhost/ --extra-headers "{\"Cookie\":\"test=true\"}"
  Request header: Cookie: test=true
  Response header: Set-Cookie: locale=en;

• All subsequent requests headers:
  Actual request headers : Cookie: locale=en
  Expected request headers: Cookie: test=true; locale=en

After merging this PR the following command introduced expected behaviour for cookies:

lighthouse http://localhost/ --extra-cookies "[{\"name\":\"test\", \"value\": \"true\", \"url\": \"http://localhost\"}]"

Links:
#6207 (comment)

Related Issues/PRs

#6207

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