Capture screenshot of localhost web services (unauthenticated pages) in @jmondi/url-to-png

@jmondi/url-to-png is an open source URL to PNG utility featuring parallel rendering using Playwright for screenshots and with storage caching via Local, S3, or CouchDB. The package includes an `ALLOW_LIST` where the host can specify which services the user is permitted to capture screenshots of. By default, capturing screenshots of web services running on localhost, 127.0.0.1, or the [::] is allowed. If someone hosts this project on a server, users could then capture screenshots of other web services running locally. This issue has been addressed in version 2.1.1 with the addition of a blocklist. Users are advised to upgrade. There are no known workarounds for this vulnerability.