[prometheus] Update README file

Signed-off-by: zeritti <47476160+zeritti@users.noreply.github.com>

charts/prometheus/README.md

@@ -76,6 +76,17 @@ Releases of the included subcharts (dependencies) have been bumped as follows:
 | [prometheus-node-exporter](https://github.com/prometheus-community/helm-charts/releases/tag/prometheus-node-exporter-4.17.3) | 4.17.3 | 4.8.1 |
 | [prometheus-pushgateway](https://github.com/prometheus-community/helm-charts/releases/tag/prometheus-pushgateway-2.1.6)   | 2.1.6 | 2.0.4 |
 
+Release 5.0.0 of the _kube-state-metrics_ chart introduced a separation of the `image.repository` value in two distinct values:
+
+```console
+kube-state-metrics:
+  image:
+    registry: registry.k8s.io
+    repository: kube-state-metrics/kube-state-metrics
+```
+
+If you use your custom values file, please, set the new values accordingly.
+
 Users are advised to review changes in the corresponding chart releases before upgrading.
 
 ### To 22.6