chore(deps): update anchore/sbom-action action to v0.21.0 (#14324)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| [anchore/sbom-action](https://redirect.github.com/anchore/sbom-action)
| action | minor | `v0.20.11` → `v0.21.0` |

---

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

---

### Release Notes

<details>
<summary>anchore/sbom-action (anchore/sbom-action)</summary>

###
[`v0.21.0`](https://redirect.github.com/anchore/sbom-action/releases/tag/v0.21.0)

[Compare
Source](https://redirect.github.com/anchore/sbom-action/compare/v0.20.11...v0.21.0)

- chore(deps): update Syft to v1.39.0
([#&#8203;561](https://redirect.github.com/anchore/sbom-action/issues/561))
- chore(deps): bump
[@&#8203;octokit/request-error](https://redirect.github.com/octokit/request-error),
[@&#8203;octokit/core](https://redirect.github.com/octokit/core) and
[@&#8203;octokit/webhooks](https://redirect.github.com/octokit/webhooks)
([#&#8203;560](https://redirect.github.com/anchore/sbom-action/issues/560))
- chore(deps): bump peter-evans/create-pull-request from 7.0.11 to 8.0.0
([#&#8203;558](https://redirect.github.com/anchore/sbom-action/issues/558))

</details>

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.github/workflows/builder-snapshot.yaml

@@ -36,7 +36,7 @@ jobs:
 
       - uses: sigstore/cosign-installer@faadad0cce49287aee09b3a48701e75088a2c6ad # v4.0.0
 
-      - uses: anchore/sbom-action/download-syft@43a17d6e7add2b5535efe4dcae9952337c479a93 # v0.20.11
+      - uses: anchore/sbom-action/download-syft@a930d0ac434e3182448fe678398ba5713717112a # v0.21.0
 
       - uses: docker/setup-qemu-action@c7c53464625b32c7a7e944ae62b3e17d2b600130 # v3.7.0
         with: