Include globals and 'jest' plugin in recommended

[scriptdaemon]

I propose that the following be added to the "recommended" config option:

plugins: [
  'jest'
],
env: {
  'jest/globals': true
}

That way, when extending the recommended settings, a user does not have to include these manually. Both eslint-config-standard and eslint-plugin-vue (and probably others) do this as well. I'll submit the PR if this proposal is accepted.

[SimenB]

React plugin does it as well, so I'm +1. PR welcome 🙂