setup-ubuntu.sh: Remove deadsnakes PPA

[licy183]

As Termux has switched to Python 3.12, there is no need to install deadsnakes PPA

[robertkirkman]

There are a few remaining packages that seem to have an error in building, at least for me (along the lines of "no such module: imp") that I thought might be related to python 3.12. They are listed at the bottom of #21130 :

aubio, jack2, qt5-qtwebengine

I thought that might be helpful to mention here. I have not tried to completely fix those three packages yet, just noted them down.

[TomJo2000]

There are a remaining few packages that seem to have an error in building, at least for me (along the lines of "no such module: imp") that I thought might be related to python 3.12. They are listed at the bottom of #21130 :

aubio, jack2, qt5-qtwebengine

I thought that might be helpful to mention here. I have not tried to completely fix those three packages yet, just noted them down.

• aubio took care of it. has an open PR, though that seems stalled for now. (fix: aubio patch #22015)
• qt5-qtwebengine has had 3 commits since the build consistency testing was started, including Python 3 migration.
• jack2 hasn't been touched in 5 months so probably still has its issue.