Use batched update to clean up empty JSON objects in tags fields

[AetherUnbound]

Description

While investigating the existing Clarifai tags for #3948 (comment), I had some trouble with the Postgres query used because I assumed the tags field would either be NULL or an array. It turns out that some of our older records which haven't been touched since 2020 (30,376,519 to be exact) have empty objects in them instead (e.g. {}). Example:

deploy@localhost:openledger> select * from image where jsonb_typeof(tags) = 'object' limit 1;
-[ RECORD 1 ]-------------------------
identifier              | 8eb4ea84-d61b-41cd-b5e7-4b37a084506d
created_on              | 2020-03-14 07:56:02.078247+00
updated_on              | 2020-12-08 05:34:25.570206+00
ingestion_type          | provider_api
provider                | flickr
source                  | flickr
foreign_identifier      | 27734505288
foreign_landing_url     | https://www.flickr.com/photos/81751903@N08/27734505288
url                     | https://live.staticflickr.com/882/27734505288_9575435144_b.jpg
thumbnail               | <null>
width                   | 1024
height                  | 682
filesize                | <null>
license                 | by
license_version         | 2.0
creator                 | russimages
creator_url             | https://www.flickr.com/photos/81751903@N08
title                   | wood duck drake surfacing
meta_data               | {"views": "131", "pub_date": "1524326359", "date_taken": "2018-04-20 16:33:28", "license_url": "https://creativecommons.org/licenses/by/2.0/"}
tags                    | {}
watermarked             | False
last_synced_with_source | 2020-12-08 05:34:25.570206+00
removed_from_source     | False
filetype                | <null>
category                | <null>
standardized_popularity | 0.752619128083812

This can complicate some of the logic necessary for updating tags down the line, and it may even be causing issues with updating those tags now.

I'd like to use the batched update DAG to set all of these values to NULL

Additional context

Related to #3948

[AetherUnbound]

I've kicked this off with the following run config:

{
    "batch_size": 50000,
    "dry_run": false,
    "query_id": "clean_empty_tags_objects",
    "resume_update": false,
    "select_query": "WHERE tags = '{}'",
    "table_name": "image",
    "update_query": "SET tags = NULL",
    "update_timeout": 3600
}

[AetherUnbound]

This update has been completed 🚀