Add indexes to catalog_resources

What does this MR do and why?

Related to #428443 (closed)

This MR adds this index to catalog_resources;

CREATE INDEX index_catalog_resources_on_state ON catalog_resources USING btree (state);

After discussions, we decided to add only a state index to the catalog_resources table because it's more than enough for its near-future size.

We are planning to have these queries for now;

SELECT catalog_resources.* FROM catalog_resources WHERE state = 1 ORDER BY latest_released_at ASC; -- or /DESC

SELECT catalog_resources.* FROM catalog_resources WHERE state = 1 ORDER BY created_at ASC; -- or /DESC

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