sorbet: brew tc --update --suggest-typed on test files

Author: issyl0

Library/Homebrew/test/download_strategies/abstract_file_spec.rb

@@ -1,4 +1,4 @@
-# typed: false
+# typed: true
 # frozen_string_literal: true
 
 require "download_strategy"

Library/Homebrew/test/test_bot_spec.rb

@@ -1,9 +1,10 @@
-# typed: true
+# typed: strict
 # frozen_string_literal: true
 
 require "dev-cmd/test-bot"
 
 RSpec.describe Homebrew::TestBot do
+  sig { returns(T.class_of(Homebrew::TestBot)) }
   let(:klass) { Homebrew::TestBot }
 
   describe "::setup_github_actions_sandbox!" do