Remove single space response body for head request

- The single space response was added due to a bug in safari
  in https://github.com/rails/rails/commit/cb0f8fda9652c4d24d04693bdb82cecd3b067e5c
  and
  https://github.com/rails/rails/commit/807df4fcf021fc4d15972aa1c17ba7398d43ab0d.
- This was removed from the `render nothing: true` in
  https://github.com/rails/rails/pull/14883.
- Removing it from response of :head also. As :head is more obvious
  alternative to call `render nothing:
  true`(http://guides.rubyonrails.org/layouts_and_rendering.html#using-head-to-build-header-only-responses),
  removing it from head method also.
- Closes #18253.

1 files changed, 2 insertions, 2 deletions

diff --git a/actionpack/lib/action_controller/metal/head.rb b/actionpack/lib/action_controller/metal/head.rb
index 3d2badf9c2..57e60222cd 100644
--- a/actionpack/lib/action_controller/metal/head.rb
+++ b/actionpack/lib/action_controller/metal/head.rb
@@ -29,14 +29,14 @@ module ActionController
       self.status = status
       self.location = url_for(location) if location
 
+      self.response_body = ""
+
       if include_content?(self._status_code)
         self.content_type = content_type || (Mime[formats.first] if formats)
         self.response.charset = false if self.response
-        self.response_body = " "
       else
         headers.delete('Content-Type')
         headers.delete('Content-Length')
-        self.response_body = ""
       end
     end