Docs - product feedback: Add details on how to clone/push import for projects that time out
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On the page that describes how to [import a project by Git URL](https://docs.gitlab.com/ee/user/project/import/repo_by_url.html) there is a screenshot of the interface, which shows a bullet point that says:
> The import will time out after 180 minutes. For repositories that take longer, use a clone/push combination.
We should add a section to that docs page, or alternately create a separate page, that describes the right steps to follow for a clone/push combination. That way it's easy for users in that situation to know how to do it properly.
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