Update stale status related fields
# Update "Stale" status related fields
* [x] Add validation to `AnalyzerNamespaceStatus` for `consecutive_absence_count`
* [x] Update the Services
* [x] `DiffService` returns `stale` count
* [x] `AncestorsUpdateService` updates `stale` count
* [x] `UpdateService` upserts the `stale` count to projects and passes the stale count `AncestorsUpdateService`
* [x] `AdjustmentService` accounts for the `stale` count
* [x] When `AnalyzerProjectStatus` is stale it still has to keep the reference to the last job it run, and date when it run, so that AppSec team could investigate it.
* [x] Introduce a feature flag `security_inventory_stale_analyzer_status` ( type: `wip` )
* [x] If the `security_inventory_stale_analyzer_status` is enabled then the `AnalyzerNamespaceStatus#not_configured` accounts for `stale` in the calculation.
* [x] Update GraphQL types
* [x] Expose stale count on `AnalyzerNamespaceStatus`
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