Add Rails webhook engine, docs, and dependency refresh

yookassa.gemspec

@@ -15,14 +15,14 @@ Gem::Specification.new do |spec|
   spec.license       = "MIT"
 
   spec.files            = `git ls-files`.split($INPUT_RECORD_SEPARATOR)
-  spec.test_files       = spec.files.grep(/^spec/)
   spec.extra_rdoc_files = Dir["README.md", "LICENSE", "CHANGELOG.md"]
 
   spec.require_paths = ["lib"]
 
   spec.required_ruby_version = ">= 2.6"
 
-  spec.add_runtime_dependency "dry-struct"
-  spec.add_runtime_dependency "dry-validation"
-  spec.add_runtime_dependency "http", "~> 5.0"
+  spec.add_dependency "dry-struct"
+  spec.add_dependency "dry-validation"
+  spec.add_dependency "http", ">= 5.0", "< 6.0"
+  spec.metadata["rubygems_mfa_required"] = "true"
 end