feat(graphql_parser): parse enum extension

[vohoanglong0107]

Summary

Parse GraphQL enum extensions (link). Once this is completed, we will only have input object extensions (link) remaining before the GraphQL parser is ready for benchmarking.

Test Plan

All tests should pass

[codspeed-hq]

CodSpeed Performance Report

Merging #3044 will not alter performance

_{Comparing vohoanglong0107:feat-graphql-enum-extension (842fb45) with vohoanglong0107:feat-graphql-enum-extension (d1de19c)}

Summary

✅ 92 untouched benchmarks

[arendjr]

🚀

[arendjr]

Suggested change

	p.bump(T![enum]);
	p.expect(T![enum]);

[vohoanglong0107]

I don't know if this is truly necessary, as this parsing rule should only be called in one place (here), and we must have already checked for the presence of both tokens before advancing. Correct me if you think otherwise.

[arendjr]

Yeah, it’s not a blocker, but it’s good practice for the parser functions to validate their preconditions instead of assuming to be called correctly. It wouldn’t change anything functionally now, but it makes the contract more explicit and brings some extra robustness in the face of future changes to the parser.

[ematipico]

Happy to merge once we address Arend suggestion (even in another PR if that's okay)