chore: fix some small issues detected by golangci-lint

But not using it as some linters are either plain incorrect (the one
suggesting to not use nil for `c.t.Context()`) or just
debatable (checking for err value is a good practice, but there are
good reasons to opt out in some cases).

common/daemon/tests.go

@@ -40,5 +40,4 @@ func (c *MockComponent) Stop() error {
 
 // Track does nothing
 func (c *MockComponent) Track(t *tomb.Tomb, who string) {
-	return
 }