Make PodDisruptionBudget configurable per cluster manifest

[baznikin]

There were nice issue #547 which allows to enable or disable PDB creation. One problem - it is globally configurable option at postgresql-operator level. My propose is to add option to postgres manifest to allow disabling (or enabling) of PDB per cluster.

Use case: I run many databases on same k8s cluster. Few of them are 'production grade', but some (most of them actually) are for review apps, i.e. temporary environments to test new features in development. Having PDB on every temporary database interrupt karpenter's job of reshaping cluster to cheaper/smaller/larger nodes. So I want to disable PDB for all temporary environments but still keep it for production databases.

[YvesZelros]

As minimum when on the operator config map enable_pod_disruption_budget is set false the pdb must not be created as is't the case actually.

Because adding an additional custom pdb on wanted instance cause issue when a node is drain =>

 failed to drain and delete node: Failed to drain node
  /aks-pool2-12312312-vmss00000n, due to following errors: [failed to evict pod
  env_90/zelros-postgresql-0 within allowed timeout (last error: This pod
  has more than one PodDisruptionBudget, which the eviction subresource does not
  support.