Bump Marketing API version from v16.0

[rawdreeg]

Changes proposed in this Pull Request:

Update Facebook Marketing API to v16.0

There should be no changes in the endpoints that we use, so the application should behave as it used to without any additional changes.

• Do the changed files pass phpcs checks? Please remove phpcs:ignore comments in changed files and fix any issues, or delete if not practical.

Detailed test instructions:

1. Use https://github.com/woocommerce/facebook-for-woocommerce/wiki/Smoke-tests for testing instructions
   Make sure that logging is enabled in the plugin. After the tests, inspect the logs for errors.
   The use of v16 API will be clearly visible in the endpoint URL:

Additional information:

I created a related PR to update the connect.woocommerce.com bridge. This will need to be reviewed to ensure that the connection flow also works:

https://github.com/Automattic/connect.woocommerce.com/pull/164#issue-1664053564

Changelog entry

Tweak - Bump Marketing API version from v16.0

[layoutd]

LGTM 👍🏻 No errors or problems in smoke testing.

I did get a couple 400 Bad Requests, but AFAICS they aren't related to any changes made in the API V16 (I'll try to reproduce them later):

04-13-2023 @ 12:06:50 - Request
method: DELETE
uri: https://graph.facebook.com/v16.0/?allow_live_product_set_deletion=true
user-agent: Facebook-for-WooCommerce/3.0.18 (WooCommerce/7.7.0; WordPress/6.3-alpha-55649)
body:

04-13-2023 @ 12:06:50 - Response
code: 400
message: Bad Request
body: {"error":{"message":"Unsupported delete request. Please read the Graph API documentation at https:\/\/developers.facebook.com\/docs\/graph-api","type":"GraphMethodException","code":100,"error_subcode":33,"fbtrace_id":"ATw7k8Q8fMjx3ZXLqZhFox8"}

and

4-13-2023 @ 12:06:13 - Request
method: POST
uri: https://graph.facebook.com/v16.0/…/product_sets
user-agent: Facebook-for-WooCommerce/3.0.18 (WooCommerce/7.7.0; WordPress/6.3-alpha-55649)
body: {…}
duration: 0.42537s

04-13-2023 @ 12:06:13 - Response
code: 400
message: Bad Request
body: {"error":{"message":"Fatal","type":"OAuthException","code":-1,"error_subcode":1798130,"is_transient":false,"error_user_title":"Cannot create an empty product set","error_user_msg":"We disallow the creation of empty product sets. Please add products to your catalog and create a set that contains at least one product.","fbtrace_id":"AMQYwMwhVhJj-PmAyvZCnai"}}

[rawdreeg]

Thanks @layoutd. Much appreciated!