Summary: Dep is now deprecated with go mod being the default way to manage deps.

Test Plan: `bazel test //...`

Reviewers: michelle, #engineering

Reviewed By: michelle, #engineering

Differential Revision: https://phab.corp.pixielabs.ai/D1940

GitOrigin-RevId: e8b8a8780d648ce9e31a9bc3c734ad58f1551487