Bump rubocop-rspec from 3.3.0 to 3.4.0

Bumps [rubocop-rspec](https://github.com/rubocop/rubocop-rspec) from 3.3.0 to 3.4.0.
- [Release notes](https://github.com/rubocop/rubocop-rspec/releases)
- [Changelog](https://github.com/rubocop/rubocop-rspec/blob/master/CHANGELOG.md)
- [Commits](rubocop/rubocop-rspec@v3.3.0...v3.4.0)

---
updated-dependencies:
- dependency-name: rubocop-rspec
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <[email protected]>

gems.locked

@@ -75,7 +75,7 @@ GEM
       rubocop-ast (>= 1.31.1, < 2.0)
     rubocop-rake (0.6.0)
       rubocop (~> 1.0)
-    rubocop-rspec (3.3.0)
+    rubocop-rspec (3.4.0)
       rubocop (~> 1.61)
     ruby-progressbar (1.13.0)
     ruby2_keywords (0.0.5)