Fix false negative for RSpec/RepeatedExampleGroupDescription cop when include skip/pending

[ydah]

Fixes: #2021

---

Before submitting the PR make sure the following are checked:

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

[pirj]

I couldn’t find at a glance, why did we implement it in a way that it was skipping pending and skip?

[ydah]

@pirj I think they were more guarded than necessary to prevent false positives below. No other discussion of skip was found in the PR when the cop was created.

    context 'rejected' do
      skip
    end

    context 'processed' do
      skip
    end

refs: #860 (review)

[ydah]

I updated this PR.