Update slackapi/slack-github-action action to v2 (#1269)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
|
[slackapi/slack-github-action](https://redirect.github.com/slackapi/slack-github-action)
| action | major | `v1` -> `v2` |

---

### Release Notes

<details>
<summary>slackapi/slack-github-action
(slackapi/slack-github-action)</summary>

###
[`v2`](https://redirect.github.com/slackapi/slack-github-action/compare/v1...v2)

[Compare
Source](https://redirect.github.com/slackapi/slack-github-action/compare/v1...v2)

</details>

---

### Configuration

📅 **Schedule**: Branch creation - "* 0-4 * * 3" (UTC), Automerge - At
any time (no schedule defined).

🚦 **Automerge**: Disabled by config. Please merge this manually once you
are satisfied.

♻ **Rebasing**: Whenever PR becomes conflicted, or you tick the
rebase/retry checkbox.

🔕 **Ignore**: Close this PR and you won't be reminded about this update
again.

---

- [ ] <!-- rebase-check -->If you want to rebase/retry this PR, check
this box

---

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.github/workflows/upsert-study.yml

@@ -86,7 +86,7 @@ jobs:
 
       - name: Report to slack
         id: slack
-        uses: slackapi/slack-github-action@37ebaef184d7626c5f204ab8d3baff4262dd30f0 # v1
+        uses: slackapi/slack-github-action@485a9d42d3a73031f12ec201c457e2162c45d02d # v2
         with:
           channel-id: 'C01LKMP6X36'
           payload: |