test_formula_installer: remove ScriptFileFormula test

It's deprecated and breaks `brew tests` in no-compat mode.

Library/Homebrew/test/test_formula_installer.rb

@@ -49,22 +49,4 @@ class InstallTests < Homebrew::TestCase
       assert_equal 3, bin.children.length
     end
   end
-
-  def test_script_install
-    mktmpdir do |dir|
-      name = "test_script_formula"
-      path = Pathname.new(dir)+"#{name}.rb"
-
-      path.write <<-EOS.undent
-        class #{Formulary.class_s(name)} < ScriptFileFormula
-          url "file://#{File.expand_path(__FILE__)}"
-          version "1"
-        end
-        EOS
-
-      f = Formulary.factory(path.to_s)
-
-      temporary_install(f) { assert_equal 1, f.bin.children.length }
-    end
-  end
 end