[Breaking Change][False positive] validation isn't taking fully-resolved endpoints into account

The RemovedPath validation error is wrong, it's there: https://github.com/Azure/azure-rest-api-specs/pull/24973/files#diff-b3d1f9e6f1415cdbe882d472fff17abc01be1d4cf5fce7bb87ad5977868fad3eL50

I think what happened is that @Zach-King2 had to change how endpoint prefixes were done in TypeSpec, so the fully resolved path is correct, but the validator isn't doing that. I'll open a bug.

_Originally posted by @heaths in https://github.com/Azure/azure-rest-api-specs/issues/24973#issuecomment-1659345522_

Start with the RemovedPath validation logic and the linked pull request diff, then trace how TypeSpec endpoint prefixes become fully resolved paths. Reproduce the false positive with the affected specification and verify that validation accepts paths that are correct after resolution without masking genuinely removed paths.

Written by the indexing model from the issue text.