Migrate from dep to go mod

[anupdhiran]

Summary

dep has been deprecated. Need to migrate to go mod.

Motivation

Need to have go mod in all repos for consistency and at the same time take advantage of latest offerings from gomod rather than being stuck with making dep work with latest go versions

Proposal

There are simple steps suggested by google in their blog : https://go.dev/blog/migrating-to-go-modules for migrating from dep to gomod. Following repos are using dep :

1. devtron-labs/lens
2. devtron-labs/external-app-crawler
3. devtron-labs/git-sensor
4. devtron-labs/telemetry-user-analytics
5. devtron-labs/ci-runner
6. devtron-labs/kubewatch
   Will migrate all these repos to go mod. Will also update libraries as needed.

#Testing plan
Make sure that we are able to build the repo using go build properly after migration. Also take a look manually between go.mod and gopkg.lock and make sure that all dependencies listed in .lock file are present in go.mod. Make sure go.sum is also generated.