Update Helm release external-dns to v1.20.0 (#3034)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| [external-dns](https://github.com/kubernetes-sigs/external-dns) | minor | `1.19.0` → `1.20.0` |

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### Configuration

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This PR has been generated by [Renovate Bot](https://github.com/renovatebot/renovate).
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Reviewed-on: #3034
Co-authored-by: Renovate Bot <renovate-bot@alexlebens.net>
Co-committed-by: Renovate Bot <renovate-bot@alexlebens.net>

clusters/cl01tl/helm/external-dns/Chart.lock

@@ -1,6 +1,6 @@
 dependencies:
 - name: external-dns
   repository: https://kubernetes-sigs.github.io/external-dns/
-  version: 1.19.0
-digest: sha256:2216b442cc820ebe561d611fbcca3955d5c94e227a0b3288e5db9f8da7d6ac00
-generated: "2025-12-01T20:25:38.288305-06:00"
+  version: 1.20.0
+digest: sha256:0da4dec408239ea48de1d95fa8ad7701c4fdc0efe67baa8743507c75e62e2a47
+generated: "2026-01-03T23:04:25.142170083Z"

clusters/cl01tl/helm/external-dns/Chart.yaml

@@ -16,7 +16,7 @@ maintainers:
 dependencies:
   - name: external-dns
     alias: external-dns-unifi
-    version: 1.19.0
+    version: 1.20.0
     repository: https://kubernetes-sigs.github.io/external-dns/
 icon: https://cdn.jsdelivr.net/gh/selfhst/icons/png/kubernetes.png
 # renovate: github=kubernetes-sigs/external-dns