Update brakeman requirement from = 6.1.2 to = 6.2.1

Updates the requirements on [brakeman](https://github.com/presidentbeef/brakeman) to permit the latest version.
- [Release notes](https://github.com/presidentbeef/brakeman/releases)
- [Changelog](https://github.com/presidentbeef/brakeman/blob/main/CHANGES.md)
- [Commits](presidentbeef/brakeman@v6.1.2...v6.2.1)

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

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

panolint-rails.gemspec

@@ -17,6 +17,6 @@ Gem::Specification.new do |spec|
     `git ls-files -z`.split("\x0")
   end
 
-  spec.add_dependency "brakeman", "6.1.2"
+  spec.add_dependency "brakeman", "6.2.1"
   spec.add_dependency "rubocop-rails", "2.26.2"
 end