docs: fix outdated "run with inline dependencies" example

[katrinafyi]

Summary of changes

The documentation was not updated since its first implementation in #916. Since then, #1100 and #1180 have changed the syntax in incompatible ways.

This is a really cool feature! It would be nice if a warning was given for using the old syntax, though I understand it was not available for a great deal of time.

• I have added a news fragment under changelog.d/ (if the patch affects the end users)

Test plan

Tested by running

cat <<EOF > test.py
# /// script
# requires-python = ">=3.11"
# dependencies = [
#   "requests<3",
#   "rich",
# ]
# ///

import requests
from rich.pretty import pprint

resp = requests.get("https://peps.python.org/api/peps.json")
data = resp.json()
pprint([(k, v["title"]) for k, v in data.items()][:10])
EOF

pipx run file:test.py

as in the updated docs/example.md

[Gitznik]

Hi @katrinafyi, thanks for contributing this :) I'm afraid there is already another open PR for updating this. Feel free to add your changes as suggestions there. If that PR goes stale, we can continue here.

[katrinafyi]

Oops! I forgot to check the PRs. It is good you're working on it, you can close this or use its changes if you want.