Add Giscus Comments Support in Blog

[shravanngoswamii]

Feel free to suggest dark mode theme, light theme is fine!

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Closes #133

[github-actions]

Preview the changes: https://turinglang.org/pr-previews/134
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[shravanngoswamii]

If it looks good, then maybe we can also add it in docs

[penelopeysm]

I think there is a best case scenario for comments: we don't need to moderate it, community has a useful discussion about the contents, new readers benefit from old readers' wisdom, people get along nicely.

There is also a worst case scenario: spam and otherwise nonconstructive comments, people reporting bugs that we don't see because we don't look at it all the time, which makes the page look unmaintained and worse.

Of course it's a spectrum, so it will likely be somewhere in between. But where do you think we'll end up?

If you aren't expecting much engagement (personally I don't), do you think there's an argument against allowing comments, so that discussion is centralised on a set of channels that we do have the capacity to monitor?

[shravanngoswamii]

If you aren't expecting much engagement (personally I don't

I also think there won’t be much engagement on this. However, some new people don’t join the Julia Slack, and some still ask Turing-related questions in channels other than #turing.

Having a comment section just below the page is the most straightforward way for people to show appreciation or ask questions. I also don’t think people will spam it, since it requires a GitHub login.

people reporting bugs that we don't see because we don't look at it all the time

I am subscribed to all activity on this repo, but it’s still quite possible that something could get ignored.

But I think having the feature is better than not having it. -- We can also use this to make some internal comments which people should be aware of like the particular blog have deprecated information or anything else...

[penelopeysm]

Okay! I am happy to try it out here. I think we should hold off on the docs until we see how it plays out here, as I think there is less need for free-form discussion on the docs (if something in the docs is outdated or wrong, it should just be updated).