Add an explanatory comment for how we initialize the environment upgrade

bindings in k8s infra.

Signed-off-by: Lukas Krejci <lkrejci@redhat.com>

infrastructures/kubernetes/src/main/java/org/eclipse/che/workspace/infrastructure/kubernetes/KubernetesInfraModule.java

@@ -206,6 +206,8 @@ protected void configure() {
     KubernetesDevfileBindings.addKubernetesBasedComponentTypeBindings(
         binder(), KUBERNETES_COMPONENT_TYPE);
 
+    // We need to intialize the bindings somehow. Because no other environment type is upgradable
+    // to kubernetes, we just call this in a way that initializes the binding with an empty map.
     KubernetesDevfileBindings.addAllowedEnvironmentTypeUpgradeBindings(
         binder(), KubernetesEnvironment.TYPE);
   }