[config] test python buildpack too

tests/apps/python-flask/hello.py

@@ -1,8 +1,18 @@
 import os
-from flask import Flask
+from flask import Flask, abort
 
 app = Flask(__name__)
 
 @app.route('/')
 def hello():
         return 'python/flask'
+
+@app.route('/<env>')
+def get_enc(env):
+        val = os.environ.get(env, None)
+        if val:
+                return val
+        else:
+                abort(404)
+
+