Remove the cfg argument from Step.Execute [#67]

This is the first step toward removing run.Config entirely. InitKube was
the only Step that even used cfg in its Execute function; the rest just
discarded it.

internal/run/addrepo_test.go

@@ -70,7 +70,7 @@ func (suite *AddRepoTestSuite) TestPrepareAndExecute() {
 		Run().
 		Times(1)
 
-	suite.Require().NoError(a.Execute(cfg))
+	suite.Require().NoError(a.Execute())
 
 }