* Add admin option to remove canonical email blocks from a deleted account
* Add tootctl canonical_email_blocks to inspect and remove canonical email blocks
Currently, there is no way for an admin to delete an account record. However,
should that happen in the future, or should an admin mistype an account id,
`/admin/action_logs?target_account_id=<non-existent-account-id>` currently
returns a 404 instead of an empty list.
With this commit, the aforementioned page returns a correct list instead
(potentially non-empty if the account has been manually deleted)