fix cmd/krane/go.mod and include it in hack/presubmit.sh

[imjasonh]

This caused a CI failure in #1239

[imjasonh]

The CI still fails: https://github.com/google/go-containerregistry/runs/4764050886?check_suite_focus=true

go: updates to go.mod needed; to update it:
	go mod tidy

- name: Install krane
  working-directory: ./cmd/krane
  run: go install .

(This doesn't fail locally)

I think this is because it's pull_request_target and pulling source from main and not the PR contents?

Yep, the logs:

Checking out the ref
/usr/bin/git log -1 --format='%H'
'a61fd0a8e2bb2c0c187ab138aff426be8b3210d6'