📝 Add HTML media type to template docs (#1690)

Co-authored-by: Sebastián Ramírez <tiangolo@gmail.com>

docs_src/templates/tutorial001.py

@@ -1,4 +1,5 @@
 from fastapi import FastAPI, Request
+from fastapi.responses import HTMLResponse
 from fastapi.staticfiles import StaticFiles
 from fastapi.templating import Jinja2Templates
 
@@ -10,6 +11,6 @@ app.mount("/static", StaticFiles(directory="static"), name="static")
 templates = Jinja2Templates(directory="templates")
 
 
-@app.get("/items/{id}")
+@app.get("/items/{id}", response_class=HTMLResponse)
 async def read_item(request: Request, id: str):
     return templates.TemplateResponse("item.html", {"request": request, "id": id})