Enable Rubocop Style/FrozenStringLiteralComment (#23793)

db/migrate/20200508212852_reset_unique_jobs_locks.rb

db/migrate/20200510110808_reset_web_app_secret.rb

...igrate/20200510181721_remove_duplicated_indexes_pghero.rb

db/migrate/20200516180352_create_devices.rb

db/migrate/20200516183822_create_one_time_keys.rb

db/migrate/20200518083523_create_encrypted_messages.rb

.../20200521180606_encrypted_message_ids_to_timestamp_ids.rb

db/migrate/20200529214050_add_devices_url_to_accounts.rb

db/migrate/20200601222558_create_system_keys.rb

db/migrate/20200605155027_add_blurhash_to_preview_cards.rb

db/migrate/20200608113046_add_sign_in_token_to_users.rb

db/migrate/20200614002136_add_sensitized_to_accounts.rb

...e/20200620164023_add_fixed_lowercase_index_to_accounts.rb

...e/20200622213645_media_attachment_ids_to_timestamp_ids.rb

...00627125810_add_thumbnail_columns_to_media_attachments.rb

db/migrate/20200628133322_create_account_notes.rb

db/migrate/20200630190240_create_webauthn_credentials.rb

db/migrate/20200630190544_add_webauthn_id_to_users.rb

...igrate/20200908193330_create_account_deletion_requests.rb

db/migrate/20200917192924_add_notify_to_follows.rb