Change return type

Library/Homebrew/requirement.rb

@@ -106,7 +106,7 @@ class Requirement
       cc:           T.nilable(String),
       build_bottle: T::Boolean,
       bottle_arch:  T.nilable(String),
-    ).returns(T.untyped)
+    ).void
   }
   def modify_build_environment(env: nil, cc: nil, build_bottle: false, bottle_arch: nil)
     satisfied?(env: env, cc: cc, build_bottle: build_bottle, bottle_arch: bottle_arch)

Library/Homebrew/test/requirement_spec.rb

@@ -177,7 +177,7 @@ RSpec.describe Requirement do
       let(:klass) { Class.new(described_class) }
 
       it "returns nil" do
-        expect(requirement.modify_build_environment).to be_nil
+        expect { requirement.modify_build_environment }.not_to raise_error
       end
     end
   end