Fix name of 'force directory mode' option

Previously the class was setting a value for 'force directory mask' which
was getting ignored by samba. Running testparm -v would give:

  Unknown parameter encountered: "force directory mask"
  Ignoring unknown parameter "force directory mask"

The correct option name is 'force directory mode' according to the man
page.

1 files changed, 1 insertions, 1 deletions

diff --git a/spec/acceptance/basic_samba_spec.rb b/spec/acceptance/basic_samba_spec.rb
index 0dd6ac6..76e7f9f 100644
--- a/spec/acceptance/basic_samba_spec.rb
+++ b/spec/acceptance/basic_samba_spec.rb
@@ -18,7 +18,7 @@ describe 'basic samba' do
         create_mask          => 0777,
         force_create_mask    => 0777,
         directory_mask       => 0777,
-        force_directory_mask => 0777,
+        force_directory_mode => 0777,
         force_group          => 'group',
         force_user           => 'user',
       }