Post 20.04 installation needs manual installation of packages

[jviereck]

After installing the 20.04 ubuntu image, the following packages need to be installed manually once more:

pip3 install breathe
sudo apt install libcereal-dev libedit-dev doxygen

These packages are listed and should be installed by the image. So it's not clear why they don't get installed in the first place

[Lhumd]

@jviereck I closed this issue as the pull request was merged.

[jviereck]

A PR was merged but this still needs to be performed manually after the installation at this point :/