Added test case for minikube config unset

cmd/minikube/cmd/config/unset_test.go

@@ -0,0 +1,32 @@
+/*
+Copyright 2019 The Kubernetes Authors All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package config
+
+import "testing"
+
+func TestUnsetConfig(t *testing.T) {
+	propName := "cpus"
+	propValue := "1"
+	err := Set(propName, propValue)
+	if err != nil {
+		t.Errorf("Failed to set the property %q", propName)
+	}
+	err = unset(propName)
+	if err != nil {
+		t.Errorf("Failed to unset property %q", err)
+	}
+}