AssetSetLastModifiedProcess and DamMetadataWritebackWorkflowCompleted Process are in UNNECESSARY list, but they are supported in AEMaaCS

### Expected Behaviour
Custom code in AEMaaCS should be able to make use of AssetSetLastModifiedProcess and DamMetadataWritebackWorkflowCompleted process step in their code base. As they are used in Writeback workflow of AEMaaCS and supported, hence should not be part of UNNECESSARY process list.

### Actual Behaviour
Code with AssetSetLastModifiedProcess and DamMetadataWritebackWorkflowCompleted process step are reported as BLOCKER bug in code scan as they are marked as UNNECESSARY.

### Reproduce Scenario (including but not limited to)

#### Steps to Reproduce

#### Platform and Version

#### Sample Code that illustrates the problem

#### Logs taken while reproducing problem

Locate the definition of the UNNECESSARY process list and search for AssetSetLastModifiedProcess and DamMetadataWritebackWorkflowCompleted. Review any tests covering process classification, then confirm that both supported AEMaaCS process steps are no longer reported as BLOCKER issues.

Written by the indexing model from the issue text.