✅ Update query param tests and docs

docs/tutorial/query-params.md

@@ -140,7 +140,7 @@ Here the query parameter `needy` is a required query parameter of type `str`.
 If you open in your browser a URL like:
 
 ```
-http://127.0.0.1:8000/users/2/items/foo-item
+http://127.0.0.1:8000/items/foo-item
 ```
 
 ...without adding the required parameter `needy`, you will see an error like:
@@ -163,7 +163,7 @@ http://127.0.0.1:8000/users/2/items/foo-item
 As `needy` is a required parameter, you would need to set it in the URL:
 
 ```
-http://127.0.0.1:8000/users/2/items/foo-item?needy=sooooneedy
+http://127.0.0.1:8000/items/foo-item?needy=sooooneedy
 ```
 
 ...this would work:
@@ -171,7 +171,18 @@ http://127.0.0.1:8000/users/2/items/foo-item?needy=sooooneedy
 ```JSON
 {
     "item_id": "foo-item",
-    "owner_id": 2,
     "needy": "sooooneedy"
 }
-```
+```
+
+And of course, you can define some parameters as required, some as having a default value, and some entirely optional:
+
+```Python hl_lines="7"
+{!./tutorial/src/query_params/tutorial006.py!}
+```
+
+In this case, there are 3 query parameters:
+
+* `needy`, a required `str`.
+* `skip`, an `int` with a default value of `0`.
+* `limit`, an optional `int`.

docs/tutorial/src/query_params/tutorial005.py

@@ -3,7 +3,7 @@ from fastapi import FastAPI
 app = FastAPI()
 
 
-@app.get("/users/{user_id}/items/{item_id}")
-async def read_user_item(user_id: int, item_id: str, needy: str):
-    item = {"item_id": item_id, "owner_id": user_id, "needy": needy}
+@app.get("/items/{item_id}")
+async def read_user_item(item_id: str, needy: str):
+    item = {"item_id": item_id, "needy": needy}
     return item

docs/tutorial/src/query_params/tutorial006.py

@@ -0,0 +1,9 @@
+from fastapi import FastAPI
+
+app = FastAPI()
+
+
+@app.get("/items/{item_id}")
+async def read_user_item(item_id: str, needy: str, skip: int = 0, limit: int = None):
+    item = {"item_id": item_id, "needy": needy, "skip": skip, "limit": limit}
+    return item