[gnome-software] trivial: Fix typo in docstring

[Robert Ancell <rancell src gnome org>]

commit 75622634c38b7dcaf1f59dc43cb7513d02671786
Author: Robert Ancell <robert ancell canonical com>
Date:   Wed Nov 22 16:07:46 2017 +1300

    trivial: Fix typo in docstring

 lib/gs-app-list.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/lib/gs-app-list.c b/lib/gs-app-list.c
index 49f682f..4f5f770 100644
--- a/lib/gs-app-list.c
+++ b/lib/gs-app-list.c
@@ -166,7 +166,7 @@ gs_app_list_add_safe (GsAppList *list, GsApp *app)
  * incrementing the reference count.
  * If the application already exists then a warning is printed to the console.
  *
- * Applications that have the application ID lazy-loaded will always be addded
+ * Applications that have the application ID lazy-loaded will always be added
  * to the list, and to clean these up the plugin loader will also call the
  * gs_app_list_filter_duplicates() method when all plugins have run.
  *