Fix FormatApplicationName

Remove the @staticmethod decorator, which introduced some unintended
behavior.

Signed-off-by: Adam Israel <adam.israel@canonical.com>
diff --git a/n2vc/vnf.py b/n2vc/vnf.py
index a60f36c..f2d0a1e 100644
--- a/n2vc/vnf.py
+++ b/n2vc/vnf.py
@@ -926,7 +926,6 @@
 
         return config
 
-    @staticmethod
     def FormatApplicationName(self, *args):
         """
         Generate a Juju-compatible Application name
@@ -942,7 +941,6 @@
 
             FormatApplicationName("ping_pong_ns", "ping_vnf", "a")
         """
-
         appname = ""
         for c in "-".join(list(args)):
             if c.isdigit():