Sort RuboCop config file

[bquorning]

Just sorting our cop config file, makes it easier to read.

Extracted from #1957.

---

Before submitting the PR make sure the following are checked:

• [x] Feature branch is up-to-date with master (if not - rebase it).
• [x] Squashed related commits together.
• [ ] Added tests.
• [ ] Updated documentation.
• [ ] Added an entry to the CHANGELOG.md if the new code introduces user-observable changes.
• [x] The build (bundle exec rake) passes (be sure to run this locally, since it may produce updated documentation that you will need to commit).

[bquorning]

CI failure is addressed in #1959.