Add url to errors

[alextes]

Currently, the property is called url. Another sensible choice could be href.

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Fixes #282

[sindresorhus]

@alextes Add Fixes #666 (Use the actual issue number of course) to PR descriptions so the issue is closed when the PR is merged. More tips here: https://github.com/tiimgreen/github-cheat-sheet

[alextes]

@sindresorhus it's in the commit message of the commit that fixes it. I'll use fixes from now on and add it to the initial PR comment instead. Makes more sense to me after thinking about the options.

Hm, the effect of the latter is nicer too I see. It includes a PR status badge. Thanks for the suggestion Sindre!

[sindresorhus]

It also makes it easy to quickly click into the issue.

[sindresorhus]

@floatdrop Looks good to you?

[floatdrop]

@sindresorhus lgtm.

[sindresorhus]

This also needs to be documented: https://github.com/sindresorhus/got#errors Forgot about that.

[alextes]

Done. Missed that on my previous PR - the one that added protocol - too.