Enable [review-changes-since] feature for the rust-lang organization

[Urgau]

Now that we support org-wide config (thks to #2292), I would like to enable the first feature for triagebot-enabled repositories in the rust-lang organization.

The "View changes since this review" link seems like a good first candidate, so that's what this PR enables.

cc @Mark-Simulacrum

[Kobzol]

Might be good to announce this somehow. Maybe in the infra announcements channel @jieyouxu ?

View changes since this review

[jieyouxu]

Maybe in the infra announcements channel @jieyouxu ?

Yes, I think that would be a good idea.

[Urgau]

Doing an announcement seems reasonable to me as well.

I took the liberty to write one (with AI help), what do you think?

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Triagebot Organization-Wide Defaults

We’re introducing organization-wide configuration defaults for Triagebot!

This change will make it easier to roll out improvements across all triagebot-enabled rust-lang repositories without needing separate pull requests for each one. Individual repositories can still opt out of any feature by opening a pull request to the rust-lang/triagebot repository.

As the first feature under this new setup, "View changes since this review" links will be enabled across the organization soon. This feature makes it easier to see what’s changed in a pull request since your last review, helping reviewers stay up to date with less effort.

[Kobzol]

Would be nice to link the file which should be modified when talking about opening the PR, otherwise looks good.

[Urgau]

Sure, added a link to file rust-lang.triagebot.toml file with highlighting on how to exclude a repo.

[Kobzol]

I think that only t-infra people can post into the announcements channel (?). I'll let jieyouxu take a look, then we can post it.

[jieyouxu]

Looks good to me as well

[Urgau]

The announcement was posted 2 days ago, #t-infra/announcements > Triagebot Organization-Wide Defaults @ 💬.

Let's go.

[Urgau]

It worked! rust-lang/rust-forge#1013 (review)