fix(router): ensure persisted operation hits both with and without op name

[df-wg]

Motivation and Context

We previously included operation name in the persisted operation cache key. As a result, though, when a persisted operation was stored with a operation name, and someone called it without that operation name, it wouldn't return a cache hit, despite the fact that it was a match. This PR removes the operation name from the cache key, given that it is irrelevant to how specialized we want it to be

Checklist

• I have discussed my proposed changes in an issue and have received approval to proceed.
• I have followed the coding standards of the project.
• Tests or benchmarks have been added or updated.
• Documentation has been updated on https://github.com/wundergraph/cosmo-docs.
• I have read the Contributors Guide.

[github-actions]

Router image scan passed

✅ No security vulnerabilities found in image:

ghcr.io/wundergraph/cosmo/router:sha-86f063867e528024b1f1955446990b2bae24ad10

[jensneuse]

very nice!

[StarpTech]

LGTM

[StarpTech]

LGTM