gnunet: update to version 0.19.2

gnunet: update to version 0.19.2

GNUnet has not been updated for a while due to the gnurl-situation.
Now that we got libcurl-gnutls, we can update GNUnet.
For details, please see the GNUnet release notes:

https://www.gnunet.org/en/news/2022-09-0.17.6.html
https://www.gnunet.org/en/news/2022-10-0.18.0.html
https://www.gnunet.org/en/news/2022-11-0.18.1.html
https://www.gnunet.org/en/news/2022-12-0.19.0.html
https://www.gnunet.org/en/news/2022-12-0.19.1.html
https://www.gnunet.org/en/news/2023-01-0.19.2.html

Signed-off-by: Daniel Golle <daniel@makrotopia.org>