Added jsonify back to delete_formula

Author: Clark Perkins

stackdio/client/formula.py

@@ -32,7 +32,7 @@ def search_formulas(self, **kwargs):
     @endpoint("formulas/{formula_id}/")
     def delete_formula(self, formula_id):
         """Delete formula with matching id"""
-        return self._delete(endpoint)
+        return self._delete(endpoint, jsonify=True)
 
     @endpoint("formulas/{formula_id}/action/")
     def update_formula(self, formula_id):