go.sum incomplete for go mod vendor on 4.13.0

[amesgen]

Describe the bug
Packaging gh-dash (e.g. for nixpkgs) requires that go mod vendor works. However, running go mod vendor for 4.13.0 results in

go: github.com/dlvhdr/gh-dash/v4/ui/common tested by
	github.com/dlvhdr/gh-dash/v4/ui/common.test imports
	github.com/stretchr/testify/require: missing go.sum entry for module providing package github.com/stretchr/testify/require (imported by github.com/dlvhdr/gh-dash/v4/ui/common); to add:
	go get -t github.com/dlvhdr/gh-dash/v4/ui/common

Of course, this is easy to work around, but ideally, it is fixed upstream.

Expected behavior
gh-dash should be go mod vendor-clean, maybe by enforcing this on CI? Thanks!