Feature: When a project connects with a github repo, a background synchronization process needs to happen

[begedin]

Problem

This is something we likely still need to work out fully, but the general idea is that, when a project connects to a github repo, there should some sort of sync happening.

• Issues and comments from the repo should be imported as tasks and comments into the project
• Tasks and comments from cc should not (?) be imported into github

Thoughts and concerns

• A project can be joined with multiple repositories.
• We will likely be importing a lot of "useless" information. Closed issues that aren't active anymore, etc.
• Technically, if we skip the import altogether, as issues and comments get modified, we will be getting webhooks for those, so eventually, if we do not explicitly sync, we will get the tasks and comments that are still active
• Overall, I do think an import is necessary, though.

[begedin]

#971 is a duplicate of this one.

While it looks like this one has more information, the questions and issues raised here have been discussed "off-site" and have mostly been resolved, so I'm closing this one in favor of #971