tests: support :needs_arm, :needs_intel metadata

This adds the ability to specify tests that depend on a certain CPU
architecture using `:needs_arm` or `:needs_intel`, similar to the
existing `:needs_macos` and `:needs_linux` metadata for tests that
depend on a certain OS.

Library/Homebrew/dev-cmd/tests.rb

@@ -134,6 +134,10 @@ module Homebrew
           end
           # rubocop:enable Homebrew/MoveToExtendOS
 
+          bundle_args << "--tag" << "~needs_arm" unless Hardware::CPU.arm?
+
+          bundle_args << "--tag" << "~needs_intel" unless Hardware::CPU.intel?
+
           bundle_args << "--tag" << "~needs_network" unless args.online?
           unless ENV["CI"]
             bundle_args << "--tag" << "~needs_ci" \