[chore][cmd/mdatagen] remove unused generated code

cmd/mdatagen/templates/component_test.go.tmpl

@@ -47,14 +47,6 @@ import (
 {{- end }}
 )
 
-// assertNoErrorHost implements a component.Host that asserts that there were no errors.
-type assertNoErrorHost struct {
-	component.Host
-	*testing.T
-}
-
-var _ component.Host = (*assertNoErrorHost)(nil)
-
 {{ if isExporter }}
 func TestComponentLifecycle(t *testing.T) {
 	factory := NewFactory()