bundle: remove services_installed?

`brew services` is now always "installed".

Library/Homebrew/bundle/brew_services.rb

@@ -38,7 +38,7 @@ module Homebrew
       end
 
       def started_services
-        @started_services ||= if Bundle.services_installed?
+        @started_services ||= begin
           states_to_skip = %w[stopped none]
           Utils.safe_popen_read("brew", "services", "list").lines.filter_map do |line|
             name, state, _plist = line.split(/\s+/)
@@ -46,8 +46,6 @@ module Homebrew
 
             name
           end
-        else
-          []
         end
       end
     end

Library/Homebrew/bundle/bundle.rb

@@ -45,10 +45,6 @@ module Homebrew
                              !Homebrew::EnvConfig.no_install_from_api?)
       end
 
-      def services_installed?
-        @services_installed ||= which("services.rb").present?
-      end
-
       def which_formula(name)
         formula = Formulary.factory(name)
         ENV["PATH"] = "#{formula.opt_bin}:#{ENV.fetch("PATH", nil)}" if formula.any_version_installed?

Library/Homebrew/test/bundle/brew_services_spec.rb

@@ -8,13 +8,7 @@ RSpec.describe Homebrew::Bundle::BrewServices do
       described_class.reset!
     end
 
-    it "is empty when brew services not installed" do
-      allow(Homebrew::Bundle).to receive(:services_installed?).and_return(false)
-      expect(described_class.started_services).to be_empty
-    end
-
     it "returns started services" do
-      allow(Homebrew::Bundle).to receive(:services_installed?).and_return(true)
       allow(Utils).to receive(:safe_popen_read).and_return <<~EOS
         nginx  started  homebrew.mxcl.nginx.plist
         apache stopped  homebrew.mxcl.apache.plist

Library/Homebrew/test/bundle/bundle_spec.rb

@@ -39,13 +39,6 @@ RSpec.describe Homebrew::Bundle do
     end
   end
 
-  context "when checking for brew services", :needs_macos do
-    it "finds it when present" do
-      allow(described_class).to receive(:which).and_return(true)
-      expect(described_class.services_installed?).to be(true)
-    end
-  end
-
   context "when checking for mas", :needs_macos do
     it "finds it when present" do
       stub_formula_loader formula("mas") { url "mas-1.0" }