Bug 1631839 - part 2: Bump taskgraph to fix broken index-tasks

[JohanLorenzo]

See https://phabricator.services.mozilla.com/D75082 for full context

Pull Request checklist

• Tests: This PR includes thorough tests or an explanation of why it does not
• Screenshots: This PR includes screenshots or GIFs of the changes made or an explanation of why it does not
• Accessibility: The code in this PR follows accessibility best practices or does not include any user facing features. In addition, it includes a screenshot of a successful accessibility scan to ensure no new defects are added to the product.

After merge

• Milestone: Make sure issues finished by this pull request are added to the milestone of the version currently in development.

To download an APK when reviewing a PR:

1. click on Show All Checks,
2. click Details next to "Taskcluster (pull_request)" after it appears and then finishes with a green checkmark,
3. click on the "Fenix - assemble" task, then click "Run Artifacts".
4. the APK links should be on the left side of the screen, named for each CPU architecture

[MihaiTabara]

Matches https://hg.mozilla.org/ci/taskgraph/rev/cab4565345d0d0effa66f18fe91335dd6d744031