Automatic merge from submit-queue. If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.

hack/test-update-storage-objects.sh: don't build a binary that the script doesn't use

**What this PR does / why we need it**:
This PR removes unused code that was building a binary that script doesn't use.

**Special notes for your reviewer**:
`hack/test-update-storage-objects.sh` used `attachlease` and `migrate-if-needed.sh` for performing etcd2 -> etcd3 migration. In the commit 39e5a566 we stopped migrating data, but still built unused `attachlease` binary.

Later, in the dc4d92e1 commit, `migrate-if-needed.sh` was reimplemented in go and unused `attachlease` was replaced by `migrate` that also wasn't needed.