Build(deps): Bump concurrent-ruby from 1.1.5 to 1.1.6 (#8930)

Bumps [concurrent-ruby](https://github.com/ruby-concurrency/concurrent-ruby) from 1.1.5 to 1.1.6.
- [Release notes](https://github.com/ruby-concurrency/concurrent-ruby/releases)
- [Changelog](https://github.com/ruby-concurrency/concurrent-ruby/blob/master/CHANGELOG.md)
- [Commits](https://github.com/ruby-concurrency/concurrent-ruby/compare/v1.1.5...v1.1.6)

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

Co-authored-by: Robin Ward <robin.ward@gmail.com>

Gemfile.lock

@@ -84,7 +84,7 @@ GEM
     chunky_png (1.3.11)
     coderay (1.1.2)
     colored2 (3.1.2)
-    concurrent-ruby (1.1.5)
+    concurrent-ruby (1.1.6)
     connection_pool (2.2.2)
     cose (0.11.0)
       cbor (~> 0.5.9)