chore(deps): update sigstore/cosign-installer digest to c85d0e2 (#1783)

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This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
|
[sigstore/cosign-installer](https://togithub.com/sigstore/cosign-installer)
| action | digest | `9becc61` -> `c85d0e2` |

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.github/actions/install-tools/action.yaml

@@ -4,7 +4,7 @@ description: "Install pipeline tools"
 runs:
   using: composite
   steps:
-    - uses: sigstore/cosign-installer@9becc617647dfa20ae7b1151972e9b3a2c338a2b # v2.8.1
+    - uses: sigstore/cosign-installer@c85d0e205a72a294fe064f618a87dbac13084086 # v2.8.1
 
     - uses: anchore/sbom-action/download-syft@78fc58e266e87a38d4194b2137a3d4e9bcaf7ca1 # v0.14.3