Fix "redefines-builtin-id" linting error:

```
redefines-builtin-id: redefinition of the built-in function new
```

This is basically shadowing a built in method, which is a bad practice.

Signed-off-by: Brendan Winter <bwinter@vmware.com>

wavefront/resource_role.go

@@ -50,12 +50,12 @@ func getAssignees(d *schema.ResourceData) ([]string, []string) {
 }
 
 func getChangedLists(d *schema.ResourceData, key string) ([]string, []string) {
-	old, new := d.GetChange(key)
+	oldC, newC := d.GetChange(key)
 	var oldP, newP []string
-	for _, o := range old.(*schema.Set).List() {
+	for _, o := range oldC.(*schema.Set).List() {
 		oldP = append(oldP, fmt.Sprint(o))
 	}
-	for _, n := range new.(*schema.Set).List() {
+	for _, n := range newC.(*schema.Set).List() {
 		newP = append(newP, fmt.Sprint(n))
 	}