[gnome-builder: 1/2] Don't install sphinx cache directory

[Christian Hergert <chergert src gnome org>]

commit 1ea2af488cfe9f1c150db5af75e29db415493cde
Author: Jelle van der Waa <jelle vdwaa nl>
Date:   Mon Jun 22 20:32:26 2020 +0200

    Don't install sphinx cache directory
    
    Installing sphinx cache is not required for a user and not installing
    the .doctrees directory also makes gnome-builder reproducible.

 doc/help/meson.build | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/doc/help/meson.build b/doc/help/meson.build
index 9020fa8b5..23ae0a264 100644
--- a/doc/help/meson.build
+++ b/doc/help/meson.build
@@ -8,6 +8,6 @@ custom_target('en user documentation',
   build_by_default: true
 )
 
-install_subdir(meson.current_build_dir() + '/en', install_dir: pkgdocdir_abs)
+install_subdir(meson.current_build_dir() + '/en', install_dir: pkgdocdir_abs, exclude_directories: 
'.doctrees')
 
 endif