chore(deps): update sidekiq requirement in /examples/using-sidekiq

Updates the requirements on [sidekiq](https://github.com/sidekiq/sidekiq) to permit the latest version.
- [Changelog](https://github.com/sidekiq/sidekiq/blob/main/Changes.md)
- [Commits](sidekiq/sidekiq@v7.3.1...v7.3.6)

---
updated-dependencies:
- dependency-name: sidekiq
  dependency-type: direct:production
...

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

Author: dependabot[bot]

examples/using-sidekiq/Gemfile

@@ -3,5 +3,5 @@
 source "https://rubygems.org"
 
 gem "redis", "5.3.0"
-gem "sidekiq", "7.3.1"
+gem "sidekiq", "7.3.6"
 gem "sinatra", "~> 4.0"