Remove queue processor indexer. Product indexer now only send product id's straight to message queue

[supercid]

Description

Removes unnecessary secondary indexer, which does extra processing and brings no real benefit.
With this PR, there will be a single indexer, which simply send product ID's to the message queue with an action to either update or delete products that will be consumed by SyncService

Related Issue

• fixes Duplicate rows nosto_tagging_product_update_queue #804
• fixes nosto_index_product_queue_processor is running out of memory when reindex #790
• fixes MassProductAttributeUpdate Observer - massive slowing down product updates #802

How Has This Been Tested?

Things to test:

• Update on save
• Update on schedule and manually saving a product, will it trigger the observers on https://github.com/Nosto/nosto-magento2/blob/e4b86dc4f06817f8deefb56c683688fe16eefcad/Observer/Product/Base.php and https://github.com/Nosto/nosto-magento2/blob/e4b86dc4f06817f8deefb56c683688fe16eefcad/Plugin/ProductUpdate.php on a loop? If so, remove the check and test again
• Save orders, check observers for update-on-save, on schedule
• Initial export pulls everything correctly
• Are CL tables growing indefinitely? Then restore the CL cleanup / Check cron for cleanup
• Change the driver and test with RabbitMQ, will it pull data correctly?
• Dimensions

Documentation:

• Create a new section on the wiki-docs and update indexer name: Add indexer 7.0 wiki-docs#86

Checklist:

• My code follows the code style of this project.
• I have updated the documentation accordingly.
• All new and existing tests passed.
• I have assigned the correct milestone or created one if non-existent.
• I have correctly labeled this pull request.
• I have linked the corresponding issue in this description.
• I have updated the corresponding Jira ticket.
• I have requested a review from at least 2 reviewers
• I have checked the base branch of this pull request
• I have checked my code for any possible security vulnerabilities

[dairbuirabass]

Couldn't spot anything! One thing that comes to mind - to test with MSI module? Just in case.

[supercid]

@dairbuirabass It's already tested and you can check on https://magento245.plugintest.nos.to/?nostodebug=true once my benchmark is completed