Revert "build(helm): update metallb to 6.4.22 (#84)"

This reverts commit b861ef0.

Author: sophiebsw

apps/versions.toml

@@ -54,7 +54,7 @@ version = "v1.6.0"
 github = "https://github.com/kubevirt/kubevirt"
 
 [metallb]
-version = "6.4.22"
+version = "6.4.20"
 helm = "https://charts.bitnami.com/bitnami"
 
 [metrics-server]