Add solution for day 4 #12

	name: update 2023 stars
	on:
	- push
	- workflow_dispatch
	jobs:
	update-2023-stars:
	name: fetch 2023 stars and update README.md
	runs-on: ubuntu-latest
	env:
	leaderboardId: 3575035
	userId: 3575035
	SESSION_COOKIE: ${{ secrets.SESSION_COOKIE }}
	steps:
	- name: checkout
	uses: actions/checkout@v4
	with:
	sparse-checkout: \|
	README.md
	sparse-checkout-cone-mode: false

	- name: fetch 2023 stars
	run: \|
	curl "https://adventofcode.com/2023/leaderboard/private/view/${leaderboardId}.json" \
	-H 'Accept: Application/json ' \
	-H "Cookie: session=${SESSION_COOKIE}" \
	-o 2023.json

	- name: update 2023 stars in README.md
	run: \|
	starsCount=$(jq --arg userId "${userId}" -r '.members[$userId].stars' 2023.json)
	sed -i "s/\!\[2023\](https:\/\/img\.shields\.io\/badge\/2023-[0-9]\+/\!\[2023\](https:\/\/img\.shields\.io\/badge\/2023-${starsCount}/" README.md

	- name: commit and push changes
	run: \|
	git config --global user.name 'github-actions[bot]'
	git config --global user.email 'github-actions[bot]@users.noreply.github.com'
	git add README.md
	git commit -m "[no ci] README: update 2023 stars"
	git push

Provide feedback