DX-2981 Update package version in user agent (#140)

* Update package version in user agent

* `b1`

Author: ajrice6713

bandwidth/api_client.py

@@ -77,7 +77,7 @@ def __init__(self, configuration=None, header_name=None, header_value=None,
             self.default_headers[header_name] = header_value
         self.cookie = cookie
         # Set default User-Agent.
-        self.user_agent = 'OpenAPI-Generator/1.0.0/python'
+        self.user_agent = 'OpenAPI-Generator/15.0.0b1/python'
 
     def __enter__(self):
         return self