📝 Update docs and examples for Response Model with Return Type Annotations, and update runtime error (#5873)

docs_src/response_model/tutorial003_03.py

@@ -0,0 +1,9 @@
+from fastapi import FastAPI
+from fastapi.responses import RedirectResponse
+
+app = FastAPI()
+
+
+@app.get("/teleport")
+async def get_teleport() -> RedirectResponse:
+    return RedirectResponse(url="https://www.youtube.com/watch?v=dQw4w9WgXcQ")