Release v3.0.2

[bquorning]

Time for a new release? Diff: https://github.com/rubocop/rubocop-rspec/compare/v3.0.1...0cb5dc563a67131f565546309453853748e9c5ba

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.
• [x] 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]

cc @pirj, @ydah