Bump rubocop-rails from 2.15.1 to 2.15.2 (#1783)

Bumps [rubocop-rails](https://github.com/rubocop/rubocop-rails) from 2.15.1 to 2.15.2.
- [Release notes](https://github.com/rubocop/rubocop-rails/releases)
- [Changelog](https://github.com/rubocop/rubocop-rails/blob/master/CHANGELOG.md)
- [Commits](https://github.com/rubocop/rubocop-rails/compare/v2.15.1...v2.15.2)

---
updated-dependencies:
- dependency-name: rubocop-rails
  dependency-type: direct:development
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Gemfile.lock

@@ -192,7 +192,7 @@ GEM
     puma (5.6.4)
       nio4r (~> 2.0)
     racc (1.6.0)
-    rack (2.2.3.1)
+    rack (2.2.4)
     rack-openid (1.3.1)
       rack (>= 1.1.0)
       ruby-openid (>= 2.1.8)
@@ -266,7 +266,7 @@ GEM
     rubocop-performance (1.14.2)
       rubocop (>= 1.7.0, < 2.0)
       rubocop-ast (>= 0.4.0)
-    rubocop-rails (2.15.1)
+    rubocop-rails (2.15.2)
       activesupport (>= 4.2.0)
       rack (>= 1.1)
       rubocop (>= 1.7.0, < 2.0)