chore(deps): update benchmark-action/github-action-benchmark action to v1.21.0 (#7989)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
|
[benchmark-action/github-action-benchmark](https://redirect.github.com/benchmark-action/github-action-benchmark)
| action | minor | `v1.20.7` → `v1.21.0` |

---

> [!WARNING]
> Some dependencies could not be looked up. Check the [Dependency
Dashboard](../issues/5322) for more information.

---

### Release Notes

<details>
<summary>benchmark-action/github-action-benchmark
(benchmark-action/github-action-benchmark)</summary>

###
[`v1.21.0`](https://redirect.github.com/benchmark-action/github-action-benchmark/blob/HEAD/CHANGELOG.md#v1210---02-Mar-2026)

[Compare
Source](https://redirect.github.com/benchmark-action/github-action-benchmark/compare/v1.20.7...v1.21.0)

- **fix** include package name for duplicate bench names
([#&#8203;330](https://redirect.github.com/benchmark-action/github-action-benchmark/issues/330))
- **fix** avoid duplicate package suffix in Go benchmarks
([#&#8203;337](https://redirect.github.com/benchmark-action/github-action-benchmark/issues/337))

</details>

---

### Configuration

📅 **Schedule**: Branch creation - At any time (no schedule defined),
Automerge - At any time (no schedule defined).

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

♻ **Rebasing**: Whenever PR is behind base branch, 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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View the [repository job
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.github/workflows/benchmark.yml

@@ -33,7 +33,7 @@ jobs:
           # So we can fetch the exact benchmark data from the previous commit.
           key: ${{ runner.os }}-benchmark-${{ github.event.before }}
       - name: Store benchmarks result
-        uses: benchmark-action/github-action-benchmark@4bdcce38c94cec68da58d012ac24b7b1155efe8b # v1.20.7
+        uses: benchmark-action/github-action-benchmark@a7bc2366eda11037936ea57d811a43b3418d3073 # v1.21.0
         with:
           name: Benchmarks
           tool: 'go'