test(protractor): fix mis-typed argument value for sample-size

Author: jeffbcross

protractor-shared.js

@@ -6,8 +6,7 @@ var argv = require('yargs')
  .options({
  'sample-size': {
  describe: 'sample size',
- default: 20,
- type: 'boolean'
+ default: 20
  },
  'force-gc': {
  describe: 'force gc.',