Remove explicit rails dep

Author: oliverguenther

openproject-open_desk.gemspec

@@ -15,6 +15,5 @@ Gem::Specification.new do |s|
   s.files = Dir["{app,config,db,lib}/**/*"] + %w(README.md)
 
   s.required_ruby_version = ">= 3.3.0"
-  s.add_dependency "rails", "~> 7.0"
   s.metadata["rubygems_mfa_required"] = "true"
 end