VLN-1461: remediate unpinned-github-actions (#801)

> 🏕️ This pull request was created by
[camper](https://github.com/temporalio/camper), an automated security
campaign tool.

## Finding

<table>

<tr><td><strong>Rule</strong></td><td><code>unpinned-github-actions</code></td></tr>
  <tr><td><strong>Severity</strong></td><td>MEDIUM</td></tr>

<tr><td><strong>Repository</strong></td><td><code>temporalio/api</code></td></tr>
<tr><td><strong>Ticket</strong></td><td><a
href="https://temporalio.atlassian.net/browse/VLN-1461">VLN-1461</a></td></tr>
</table>

## Summary

🤠 [Deputy](https://github.com/temporalio/deputy) pinned dependencies to
immutable references.

- Total refs: 13
- Pinned refs: 9
- Skipped refs: 4

Changed references:
- `arduino/setup-protoc`: `v2` ->
`a8b67ba40b37d35169e222f3bb352603327985b6 # v2.1.0`
- `dcarbone/install-jq-action`: `v2` ->
`8867ddb4788346d7c22b72ea2e2ffe4d514c7bcb # v2.1.0`
- `actions/checkout`: `v4` -> `34e114876b0b11c390a56381ad16ebd13914f8d5
# v4.3.1`
- `actions/setup-go`: `v4` -> `7b8cf10d4e4a01d4992d18a89f4d7dc5a3e6d6f4
# v4.3.0`
- `actions/create-github-app-token`: `v1` ->
`d72941d797fd3113feb6b93fd0dec494b13a2547 # v1.12.0`
- `actions/checkout`: `v4` -> `34e114876b0b11c390a56381ad16ebd13914f8d5
# v4.3.1`
- `actions/checkout`: `v4` -> `34e114876b0b11c390a56381ad16ebd13914f8d5
# v4.3.1`
- `bufbuild/buf-action`: `v1` ->
`fd21066df7214747548607aaa45548ba2b9bc1ff # v1.4.0`
- `actions/create-github-app-token`: `v1` ->
`d72941d797fd3113feb6b93fd0dec494b13a2547 # v1.12.0`

## Instructions

- **Approve** to merge this fix
- **Request changes** to trigger a new remediation attempt
- `/camper rebase` — rebase onto the base branch
- `/camper close` — close this PR without merging
- `/camper retry` — close and retry with a new fix

Co-authored-by: picatz <14850816+picatz@users.noreply.github.com>

Author: picatz