Drop shebangs

Files would need to have executable bit set to benefit from shebangs.
But also the content would need to be prepared to be executable. This
might be true for the test cases, but it is not true for the other
scripts at all.

lib/builder.rb

@@ -1,4 +1,3 @@
-#!/usr/bin/env ruby
 # frozen_string_literal: true
 
 #--

lib/builder/xchar.rb

@@ -1,4 +1,3 @@
-#!/usr/bin/env ruby
 # frozen_string_literal: true
 
 # The XChar library is provided courtesy of Sam Ruby (See

lib/builder/xmlbase.rb

@@ -1,4 +1,3 @@
-#!/usr/bin/env ruby
 # frozen_string_literal: true
 
 module Builder

lib/builder/xmlevents.rb

@@ -1,4 +1,3 @@
-#!/usr/bin/env ruby
 # frozen_string_literal: true
 
 #--

lib/builder/xmlmarkup.rb

@@ -1,4 +1,3 @@
-#!/usr/bin/env ruby
 # frozen_string_literal: true
 #--
 # Copyright 2004, 2005 by Jim Weirich (jim@weirichhouse.org).

rakelib/tags.rake

@@ -1,4 +1,3 @@
-#!/usr/bin/env ruby
 # frozen_string_literal: true
 
 module Tags

test/performance.rb

@@ -1,4 +1,3 @@
-#!/usr/bin/env ruby
 # frozen_string_literal: true
 # encoding: iso-8859-1
 

test/test_eventbuilder.rb

@@ -1,4 +1,3 @@
-#!/usr/bin/env ruby
 # frozen_string_literal: true
 
 #--

test/test_markupbuilder.rb

@@ -1,4 +1,3 @@
-#!/usr/bin/env ruby
 # frozen_string_literal: true
 
 #--

test/test_method_caching.rb

@@ -1,4 +1,3 @@
-#!/usr/bin/env ruby
 # frozen_string_literal: true
 
 #--

test/test_namecollision.rb

@@ -1,4 +1,3 @@
-#!/usr/bin/env ruby
 # frozen_string_literal: true
 
 #--

test/test_xchar.rb

@@ -1,4 +1,3 @@
-#!/usr/bin/env ruby
 # frozen_string_literal: true
 # encoding: us-ascii
 
@@ -12,7 +11,6 @@
 # above copyright notice is included.
 #++
 
-#!/usr/bin/env ruby
 
 require 'helper'
 require 'builder/xchar'