Resolve "Service ping integration with batched background migrations"

What does this MR do and why?

We are adding a new column (finished_at) to the batched_background_migrations table. This column aims to track when a batched background migration finishes.

Migration up:

main: == 20230603174306 AddFinishedAtColumnToBatchedBackgroundMigrationsTable: migrating
main: -- add_column(:batched_background_migrations, :finished_at, :datetime_with_timezone)
main:    -> 0.0017s
main: == 20230603174306 AddFinishedAtColumnToBatchedBackgroundMigrationsTable: migrated (0.0050s)

Migration down:

main: == 20230603174306 AddFinishedAtColumnToBatchedBackgroundMigrationsTable: reverting
main: -- remove_column(:batched_background_migrations, :finished_at, :datetime_with_timezone)
main:    -> 0.0077s
main: == 20230603174306 AddFinishedAtColumnToBatchedBackgroundMigrationsTable: reverted (0.0131s)

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Before	After

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Related to #412707 (closed)