chore(deps): update helm release hcloud-exporter to v4.2.15 (#1609)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

kustomize/bases/hcloud-exporter/kustomization.yaml

@@ -5,7 +5,7 @@ namespace: hcloud-exporter
 helmCharts:
   - name: hcloud-exporter
     repo: https://promhippie.github.io/charts
-    version: 4.2.14
+    version: 4.2.15
     releaseName: hcloud-exporter
     namespace: hcloud-exporter
     valuesFile: helm-values.yaml