hedgedoc: Enable named pads
This allows the pads to be named nicely, so for example the draft of the monthly report in july could be located at https://md.archlinux.org/2023-07_monthly-report
instead of https://md.archlinux.org/UF9Y235qTRe8XS3qxUVeJA
https://docs.hedgedoc.org/references/url-scheme/#freeurl-mode