Debian bullseye is now oldstable

I just installed it on Debian stable, i.e., bookwork, and the .deb works
there, too.

https://www.debian.org/News/2023/20230610

content/page/download-briar-desktop.md

@@ -26,7 +26,7 @@ For **Linux**, choose the appropriate version for your system, you only need one
 
 - [Ubuntu 22.04 and compatible .deb](https://desktop.briarproject.org/debs/jammy/briar-desktop-ubuntu-22.04.deb): Ubuntu 22.04 and compatible: Linux Mint 21.X (Vanessa, Vera), elementaryOS 7.X (Horus), Trisquel 11 (Aramo).
 - [Ubuntu 20.04 and compatible .deb](https://desktop.briarproject.org/debs/focal/briar-desktop-ubuntu-20.04.deb): Linux Mint 20.X (Ulyana, Ulyssa, Uma, Una), elementaryOS 6.X (Odin, Jólnir), Trisquel 10 (Nabia).
-- [Debian stable (bullseye) and compatible .deb](https://desktop.briarproject.org/debs/bullseye/briar-desktop-debian-bullseye.deb): MX Linux MX-21.
+- [Debian oldstable (bullseye) and compatible .deb](https://desktop.briarproject.org/debs/bullseye/briar-desktop-debian-bullseye.deb): MX Linux MX-21.
 - [Ubuntu 18.04 and compatible .deb](https://desktop.briarproject.org/debs/bionic/briar-desktop-ubuntu-18.04.deb): Linux Mint 19.X (Tara, Tessa, Tina, Tricia), elementaryOS 5.X (Juno, Hera), Trisquel 9 (Etiona).
 
 If your system is not based on any of the distros above, you can download this jar file: