Backend: Add released sort to CI Catalog GraphQL

Summary

To support the sorting feature in CI Catalog and also ensure that the most recent or oldest catalog resources are showing, release date needs to be added.

Proposal

1. Add latest_released_at column to the catalog_resources table. It should have the same constraints as the released_at column in the releases table. The column should be NULLable. A null value indicates the resource does not have a valid release (aka 'version').

2. Add LATEST_RELEASED_AT_ASC and LATEST_RELEASED_AT_DESC as sort options to the GraphQl ciCatalogResources endpoint.

3. Separate issue (#427791 (closed)): Augment Resources::Versions::CreateService (ref: !131032 (diffs)) and the related service upon Release deletion (ref: !130555 (diffs)) to update the resource's latest_released_at column accordingly.

MR Implementation

Description	MR
Step 1: Add latest_released_at column to catalog_resources table	!132429 (merged)
Step 2: Add latest_released_at sort options to GraphQL ciCatalogResources	!132601 (merged)

Implementation

Issue	Link
Backend: Add released sort to CI Catalog GraphQL (#408382 - closed)	👈 You are here
Backend: Update catalog_resource.latest_release... (#427791 - closed)	#427791 (closed)

Links/References

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