Update rspec-rails requirement from >= 5.1, < 7 to >= 5.1, < 8

Updates the requirements on [rspec-rails](https://github.com/rspec/rspec-rails) to permit the latest version.
- [Changelog](https://github.com/rspec/rspec-rails/blob/main/Changelog.md)
- [Commits](rspec/rspec-rails@v5.1.0...v7.0.1)

---
updated-dependencies:
- dependency-name: rspec-rails
  dependency-type: direct:development
...

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

action_controller_tweaks.gemspec

@@ -30,7 +30,7 @@ Gem::Specification.new do |s|
   s.add_development_dependency "bundler", ">= 1.0.0"
   s.add_development_dependency "rake", ">= 10.0", "<= 14.0"
   s.add_development_dependency "appraisal", "~> 2.0", ">= 2.5.0"
-  s.add_development_dependency "rspec-rails", ">= 5.1", "< 7"
+  s.add_development_dependency "rspec-rails", ">= 5.1", "< 8"
   s.add_development_dependency "rspec-its", "~> 1.0"
   # rspec-rails needs activerecord...
   s.add_development_dependency "activerecord", ">= 4.0.0"