Enabled PDB for Envoy deployments ADDENDUM (#39)

DisruptionBudget is declared as an inline field
so instead of composing the new struct, inherit it so it can be 
automatically read.

Currently you'd still need to declare:
```
podDisruptionBudget:
  PodDisruptionBudget:
    ...
  stragety:
```

for this to work while the CRD lists all the fields inlined
which is misleading for the user

Co-authored-by: Adi Muraru <[email protected]>

api/v1beta1/kafkacluster_types.go

@@ -115,7 +115,7 @@ type DisruptionBudget struct {
 // DisruptionBudgetWithStrategy defines the configuration for PodDisruptionBudget where the workload is managed by an external controller (eg. Deployments)
 type DisruptionBudgetWithStrategy struct {
 	// PodDisruptionBudget default settings
-	DisruptionBudget DisruptionBudget `json:",inline"`
+	DisruptionBudget `json:",inline"`
 	// The strategy to be used, either minAvailable or maxUnavailable
 	// +kubebuilder:validation:Enum=minAvailable;maxUnavailable
 	Stategy string `json:"strategy,omitempty"`