[gnome-builder] clang: release variant when building diagnostics

[Christian Hergert <chergert src gnome org>]

commit 62baea0d48ffc299b9e337b015fce3bf196d04d5
Author: Christian Hergert <chergert redhat com>
Date:   Sat Jul 28 01:56:55 2018 -0700

    clang: release variant when building diagnostics

 src/plugins/clang/ide-clang-client.c | 2 ++
 1 file changed, 2 insertions(+)
---
diff --git a/src/plugins/clang/ide-clang-client.c b/src/plugins/clang/ide-clang-client.c
index 72dc542ba..bbc593d13 100644
--- a/src/plugins/clang/ide-clang-client.c
+++ b/src/plugins/clang/ide-clang-client.c
@@ -1085,6 +1085,8 @@ ide_clang_client_diagnose_cb (GObject      *object,
 
       if (diag != NULL)
         ide_diagnostics_take (ret, g_steal_pointer (&diag));
+
+      g_variant_unref (v);
     }
 
   ide_task_return_pointer (task,