Add tests for http basic authentication in python client (#16488)

* add tests for http basic auth in python client

* add new files

samples/client/echo_api/java/native/api/openapi.yaml

@@ -469,6 +469,23 @@ paths:
       - body
       x-content-type: multipart/form-data
       x-accepts: text/plain
+  /auth/http/basic:
+    post:
+      description: To test HTTP basic authentication
+      operationId: test/auth/http/basic
+      responses:
+        "200":
+          content:
+            text/plain:
+              schema:
+                type: string
+          description: Successful operation
+      security:
+      - http_auth: []
+      summary: To test HTTP basic authentication
+      tags:
+      - auth
+      x-accepts: text/plain
 components:
   requestBodies:
     Pet:
@@ -729,4 +746,8 @@ components:
       required:
       - files
       type: object
+  securitySchemes:
+    http_auth:
+      scheme: basic
+      type: http