fix poetry 2 httpx dependencies

Author: wing328

modules/openapi-generator/src/main/resources/python/pyproject.mustache

@@ -61,10 +61,13 @@ requires-python = ">=3.9"
 dependencies = [
   "urllib3 (>=2.1.0,<3.0.0)",
   "python-dateutil (>=2.8.2)",
-{{#async}}
+{{#httpx}}
+  "httpx (>=0.28.1)",
+{{/httpx}}
+{{#asyncio}}
   "aiohttp (>=3.8.4)",
   "aiohttp-retry (>=2.8.3)",
-{{/async}}
+{{/asyncio}}
 {{#tornado}}
   "tornado (>=4.2,<5)",
 {{/tornado}}