Add a pipeline function to set the status of migration to complete

[kalroy]

User Story

As an Automate User, I should get the acknowledgement when the migration is completed.
On completion of the migration, the status needs to be updated.

Acceptance Criteria

• The Migration table in the DB should have migration stage set to Completed

Implementation Details

• Add a function in the migration package and in the storage to set the final status

Definition of Done

• All things specified in User Story Acceptance Criteria should be fulfilled.
• All Exceptions are Handled Properly
• Ensure logs have no unnecessary data.
• Test coverage for the new feature is done to at least 70%
• If needed raise Docs PR and tag documentation.
• Swagger Documentation updated
• Smoke Test done.
• Ensure Build and Integration Pipelines are Green.
• PR has 2 approvers.
• All Code Review Comments are Resolved.
• README doc should be updated, if needed.