Add depth recursion to inUseBySubscriptions and dependsOnSubscriptions

[tjeerddie]

This update introduces the ability to fetch subscription relations multiple layers deep by adding depth recursion to the subscription/s relations query.

Other changes:

• Move code that is independant of the graphql query loader to its own file orchestrator/services/subscription_relations.py.
• Fixed an issue in the _get_in_use_by_instance_relations and _get_depends_on_instance_relations functions where the filter_statuses argument was incorrectly applied to the subscriptions from the subscription_ids argument, rather than to their relations. This issue had no impact since filter_statuses was not in use yet.
• With the addition of the statuses filter in the SubscriptionRelationFilter, I noticed that the loader couldn't handle lists properly in combination with its caching. This is fixed by changing the list to a tuple.

More indepth description of the recursion feature:

• Use the inUseByFilter and dependsOnFilter with .recurse_product_types filter to recurse through specified product types. By default, recursion will go through the first 10 layers of the specified recurse_product_types.
• To discourage inefficient queries, recursion without specifying recurse_product_types is not allowed, as recursing through all relations could significantly impact performance.

For inUseBySubscriptions and dependsOnSubscriptions, the following filters were added:

SubscriptionRelationFilter:
    statuses: tuple[str, ...] | None = strawberry.field(default=None, description="Search by statuses")
    recurse_depth_limit: int = strawberry.field(default=10, description="the limited depth to recurse through")
    recurse_product_types: list[str] | None = strawberry.field(
        default=None, description="List of product types to recurse into"
    )

example query that would recurse through Test product type, more examples can be found in tests/unit_tests/graphql/test_subscription_relations.py:

query SubscriptionRelationsRecursive {
  subscriptions {
    page {
      subscriptionId
      description
      inUseBySubscriptions(
        inUseByFilter: {statuses: ["active"], recurseProductTypes: ["Test"]}
      ) {
        page {
          subscriptionId
          description
          status
        }
      }
    }
  }
}

The inUseByFilter/dependsOnFilter works in combination with filterBy and sortBy to filter and sort the recursively discovered subscriptions. For example:

• Filter by product tag: filterBy: [{ field: "tag", value: "MyTag" }]
• Sort by tag sortBy: [{ field: "tag", value: ASC }].

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 96.15385% with 5 lines in your changes missing coverage. Please review.

Project coverage is 83.77%. Comparing base (34e4e5f) to head (a6d858a). Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
orchestrator/services/subscription_relations.py	94.94%	3 Missing and 2 partials :warning:

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #753 +/- ## ========================================== + Coverage 83.69% 83.77% +0.07% ========================================== Files 189 190 +1 Lines 9392 9432 +40 Branches 921 922 +1 ========================================== + Hits 7861 7902 +41 Misses 1280 1280 + Partials 251 250 -1 ```

:umbrella: View full report in Codecov by Sentry.
:loudspeaker: Have feedback on the report? Share it here.