Composition issue infinite recursion with @requires use

[tinnou]

Description

When using @requires on a key field selecting a non-key field, our graph composition fails with a stack overflow:

Maximum call stack size exceeded
RangeError: Maximum call stack size exceeded
    at GraphPath.get tail [as tail] (/Users/antoineb/IdeaProjects/federation/query-graphs-js/src/graphPath.ts:199:11)
    at advanceWithOperation (/Users/antoineb/IdeaProjects/federation/query-graphs-js/src/graphPath.ts:2572:28)
    at advanceSimultaneousPathsWithOperation (/Users/antoineb/IdeaProjects/federation/query-graphs-js/src/graphPath.ts:2186:71)
    at ConditionValidationState.advance (/Users/antoineb/IdeaProjects/federation/query-graphs-js/src/conditionsValidation.ts:30:65)
    at resolver (/Users/antoineb/IdeaProjects/federation/query-graphs-js/src/conditionsValidation.ts:114:31)
    at /Users/antoineb/IdeaProjects/federation/query-graphs-js/src/conditionsCaching.ts:39:26
    at canSatisfyConditions (/Users/antoineb/IdeaProjects/federation/query-graphs-js/src/graphPath.ts:2007:22)

I added a unit test to reproduce the issue. I'm having doubts whether this is actually a legitimate use case of @requires. To me it feels not, and if this is correct, we could probably raise a validation error earlier in the composition process as key fields are either provided by the router or or expected to be provided by the subgraph.

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