bump: replaces golang/mock with a maintained uber-go fork

[chandler-solo]

Description

Replaces golang/mock with a maintained uber-go fork. See golang/mock@674a1c4

Change Type

/kind bump

Changelog

NONE

Additional Notes

[Copilot]

Pull request overview

This PR updates the project’s Go mocking tooling by migrating from the unmaintained github.com/golang/mock to the maintained fork at go.uber.org/mock, aligning both test imports and mock generation.

Changes:

• Switch test code imports from github.com/golang/mock/gomock to go.uber.org/mock/gomock.
• Update the //go:generate mockgen invocation and regenerate affected mocks using the Uber fork.
• Update module dependencies and tool declarations in go.mod/go.sum accordingly.

Reviewed changes

Copilot reviewed 5 out of 6 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
pkg/kgateway/translator/listener/gateway_listener_translator_test.go	Updates gomock import to go.uber.org/mock/gomock.
pkg/kgateway/translator/httproute/translate_httproute_test.go	Updates gomock import to go.uber.org/mock/gomock.
pkg/kgateway/query/query_test.go	Updates //go:generate to use go.uber.org/mock/mockgen.
pkg/kgateway/query/mocks/mock_queries.go	Regenerated mock to use Uber gomock and updated generator header.
go.mod	Removes github.com/golang/mock, adds go.uber.org/mock, updates tool directive to go.uber.org/mock/mockgen.
go.sum	Removes old golang/mock sums and adds sums for go.uber.org/mock.