[Feature] Check PDB during AKS upgrades only for the workloads on the specific node pool

[eyltl]

Is your feature request related to a problem? Please describe.
Today if we are trying to upgrade AKS default node pool(where we have no workloads) , we are blocked due to PDB of workloads on other node pools

Optional: Set the appropriate GitHub label(s) to indicate the AKS feature or area your feature request relates to.

Describe the solution you'd like
During the node pool upgrade, azure should check for PDB only on the specific node pool.

Describe alternatives you've considered
Check for PDB set up on the upgrade node pool, if there is any issue that can cause the cluster to be enter into a failed state then block the upgrade, or provide an API to override PDB checks(Like the option today with API changes)

[microsoft-github-policy-service]

@kaarthis, @sdesai345 would you be able to assist?