[libpeas] Fix another gjs single-include issue instance

[Ryan Lortie <ryanl src gnome org>]

commit 184bd94264bc4dbf5a34315e9153fe8b62f746e7
Author: Ryan Lortie <desrt desrt ca>
Date:   Thu Nov 22 08:03:26 2012 -0500

    Fix another gjs single-include issue instance
    
    The tests have the same problem as the loader itself and the last commit
    missed that.  Fix it too.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=688617

 tests/libpeas/extension-gjs.c |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)
---
diff --git a/tests/libpeas/extension-gjs.c b/tests/libpeas/extension-gjs.c
index 3004943..327a9c4 100644
--- a/tests/libpeas/extension-gjs.c
+++ b/tests/libpeas/extension-gjs.c
@@ -23,6 +23,7 @@
 #include <config.h>
 #endif
 
+#include <gjs/gjs-module.h>
 #include <gi/value.h>
 
 #include "loaders/gjs/peas-extension-gjs.h"