Removal: Enable cabability for custom resource removal (e.g. purge soft-deleted / removal in specific order required / etc.)

[rahalan]

Currently we cannot handle 'special' removal scenarios such as vWAN & NetApp where resources have to be removed in a specific order. Other cases cover e.g. roleAssignments / policies etc. that need a different handling alltogether.

Also pipelines and workflows for resources having soft-deletion automatically enforced are failing if run twice before the soft-deletion grace period has passed.
See e.g.: Fix policy assignment to accept westeu (#55) · 8855158 (github.com)

Impacted modules include
API management
Log Analytics Workspace
Key Vault (for which opting out from soft deletion will be deprecated soon. Ref Enable soft-delete on all key vault objects - Azure Key Vault | Microsoft Docs)

A quick fix for failing pipelines may be to set the removal step input parameter default value to false. Cons: cost management.