test: make status file names consistent

For some reason, the test/addons directory has a status file of
addon.status rather than addons.status. Make it consistent with other
directories.

Author: Trott

test/addons/addon.status renamed to test/addons/addons.status

@@ -3,4 +3,4 @@
 import testpy
 
 def GetConfiguration(context, root):
-  return testpy.AddonTestConfiguration(context, root, 'addon')
+  return testpy.AddonTestConfiguration(context, root, 'addons')