Update anchore/scan-action action to v4 (#171)

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This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| [anchore/scan-action](https://togithub.com/anchore/scan-action) |
action | major | `v3` -> `v4` |

---

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

---

### Release Notes

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

### [`v4`](https://togithub.com/anchore/scan-action/compare/v3...v4)

[Compare
Source](https://togithub.com/anchore/scan-action/compare/v3...v4)

</details>

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.github/workflows/push-pr-lint.yaml

@@ -35,7 +35,7 @@ jobs:
 
     - name: Scan image
       id: scan
-      uses: anchore/scan-action@v3
+      uses: anchore/scan-action@v4
       with:
         image: ghcr.io/equinixmetal/ironlib:latest
         acs-report-enable: true

.github/workflows/release-docker-image.yml

@@ -59,7 +59,7 @@ jobs:
 
       - name: Scan image
         id: scan
-        uses: anchore/scan-action@v3
+        uses: anchore/scan-action@v4
         with:
           image: ghcr.io/metal-toolbox/ironlib@${{ steps.dockerbuild.outputs.digest }}
           acs-report-enable: true