docs(readme): Add new related project, lighthouse-github-reporter

[carlesnunez]

Summary
This PR ads a new related project into Lighthouse called Lighthouse-github-reporter. More info on the issue.
Related Issues/PRs
#6097

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[carlesnunez]

I signed it!

[googlebot]

CLAs look good, thanks!

[wardpeet]

I believe your url is wrong. It's the same url as webpack-lighthouse-plugin

[exterkamp]

A few nitpicks.

[exterkamp]

Checking the history of this file, we add new integrations to the bottom of the list usually. So I'd move this to right under lighthouse4u.

[exterkamp]

nit: give Lighthouse-CI the power of put to make reports as a comment on your pull requests in Github.

[carlesnunez]

PR Changes done! Sorry for the typo errors and position mistake! 👍

[carlesnunez]

Hello! Why is the CI failing exactly? What I did wrong?

[wardpeet]

It's appveyor, no worries it's pretty flaky

[brendankenny]

LGTM!

[carlesnunez]

Thank you for your word fixes @brendankenny ! 😸

[brendankenny]

@wardpeet if you're good here

[wardpeet]

LGTM