Update cli.py (#132)

* Update cli.py

readfp is not available in Python 3.12.

* Update cli.py

Support Python 2 as well as Python 3.12+

Author: juur

jinja2cli/cli.py

@@ -131,7 +131,11 @@ def as_dict(self):
                 return d
 
         p = MyConfigParser()
-        p.readfp(StringIO(data))
+        try:
+            reader = p.readfp
+        except AttributeError:
+            reader = p.read_file
+        reader(StringIO(data))
         return p.as_dict()
 
     return _parse_ini, ConfigParser.Error, MalformedINI