docs: update CHANGELOG.md

Author: bednar

CHANGELOG.md

@@ -2,6 +2,7 @@
 
 ### Features
 1. [#319](https://github.com/influxdata/influxdb-client-python/pull/319): Add supports for array expressions in query parameters
+1. [#320](https://github.com/influxdata/influxdb-client-python/pull/320): Add JSONEncoder to encode query results to JSON 
 
 ## 1.20.0 [2021-08-20]
 

tests/test_FluxCSVParser.py

@@ -207,7 +207,7 @@ def test_to_json(self):
                ",,1,value,python_client_test,2010-02-27T04:48:32.752600083Z,2020-02-27T16:48:32.752600083Z,2020-02-27T16:30:00Z,2,test2\n"
 
         tables = self._parse_to_tables(data=data)
-        with open('query_output.json', 'r') as file:
+        with open('tests/query_output.json', 'r') as file:
             query_output = file.read()
             import json
             self.assertEqual(query_output, json.dumps(tables, cls=FluxStructureEncoder, indent=2))