Fix: deal with interface inheritance when retrieving selectionset

[o0Ignition0o]

Followup to #3718, this changeset makes sure we're able to generate the most concrete selection set for a given operation.

This means finding the most concrete type we can when we're dealing with interfaces:

• If InterfaceA implements InterfaceB, use InterfaceA as current_type to generate an inline fragment's selection set

Given the following invariants:

  interface OperationItemStuff implements OperationItem

For

fragment OperationItemFragment on OperationItem {
  ... on OperationItemStuff {
     stuff
  }
}

The most concrete interface to generate fields for OperationItemStuff is not OperationItem, so we narrow down the selection to OperationItemStuff.

The fixes for #3718 still apply, IE:

Given the following invariants:

  type Dog implements Animal

For

...on Animal {
  id
  ...on Dog {
    name
  }
}

The most concrete type to generate a selection set for Dog is not Animal, so we narrow down the selection to Dog.

[github-actions]

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[router-perf]

CI performance tests

• step - Basic stress test that steps up the number of users over time
• events_without_dedup - Stress test for events with a lot of users and deduplication DISABLED
• xlarge-request - Stress test with 10 MB request payload
• xxlarge-request - Stress test with 100 MB request payload
• events_big_cap_high_rate - Stress test for events with a lot of users, deduplication enabled and high rate event with a big queue capacity
• const - Basic stress test that runs with a constant number of users
• reload - Reload test over a long period of time at a constant rate of users
• large-request - Stress test with a 1 MB request payload
• events - Stress test for events with a lot of users and deduplication ENABLED
• step-jemalloc-tuning - Clone of the basic stress test for jemalloc tuning
• no-graphos - Basic stress test, no GraphOS.