Fix #137299: Exception with batch rename of nodes outside node editor

I'm not sure when this stopped working. The function in question is
quite confusing since it's called twice with two different purposes.
Fixing the exception is simple though. Just checking the data type
for "None" prevents changing the data type to one that's invalid given
the context. I didn't find a simple way to add an error message though.

Pull Request: https://projects.blender.org/blender/blender/pulls/138287

scripts/startup/bl_operators/wm.py

@@ -3031,6 +3031,10 @@ class WM_OT_batch_rename(Operator):
                     "name",
                     descr,
                 )
+
+        if data is None:
+            return None
+
         data = ([it for it in data[0] if _is_editable(it)], data[1], data[2])
 
         return data