[Python] Add configuration.{connection_pool_maxsize, assert_hostname} (#6508)

* Backport kubernetes client features:

- assert_hostname
- connection_pool_maxsize
- cleanups

* Update petstore sample

samples/client/petstore/python-asyncio/docs/AnotherFakeApi.md

@@ -0,0 +1,57 @@
+# petstore_api.AnotherFakeApi
+
+All URIs are relative to *http://petstore.swagger.io:80/v2*
+
+Method | HTTP request | Description
+------------- | ------------- | -------------
+[**test_special_tags**](AnotherFakeApi.md#test_special_tags) | **PATCH** /another-fake/dummy | To test special tags
+
+
+# **test_special_tags**
+> Client test_special_tags(body)
+
+To test special tags
+
+To test special tags
+
+### Example 
+```python
+from __future__ import print_function
+import time
+import petstore_api
+from petstore_api.rest import ApiException
+from pprint import pprint
+
+# create an instance of the API class
+api_instance = petstore_api.AnotherFakeApi()
+body = petstore_api.Client() # Client | client model
+
+try: 
+    # To test special tags
+    api_response = api_instance.test_special_tags(body)
+    pprint(api_response)
+except ApiException as e:
+    print("Exception when calling AnotherFakeApi->test_special_tags: %s\n" % e)
+```
+
+### Parameters
+
+Name | Type | Description  | Notes
+------------- | ------------- | ------------- | -------------
+ **body** | [**Client**](Client.md)| client model | 
+
+### Return type
+
+[**Client**](Client.md)
+
+### Authorization
+
+No authorization required
+
+### HTTP request headers
+
+ - **Content-Type**: application/json
+ - **Accept**: application/json
+
+[[Back to top]](#) [[Back to API list]](../README.md#documentation-for-api-endpoints) [[Back to Model list]](../README.md#documentation-for-models) [[Back to README]](../README.md)
+