docs(select): correct sample file text

Closes #12868

Author: jayspringate

src/ng/directive/select.js

@@ -219,7 +219,7 @@ var SelectController =
  *  angular.module('ngrepeatSelect', [])
  *    .controller('ExampleController', ['$scope', function($scope) {
  *      $scope.data = {
- *       singleSelect: null,
+ *       repeatSelect: null,
  *       availableOptions: [
  *         {id: '1', name: 'Option A'},
  *         {id: '2', name: 'Option B'},