Fixed several issues with the install instructions for Fedora:
- removed packages that are already pulled by "Development Tools" and "C
Development Tools and Libraries" groups
- added missing "which" package needed for SDK installation script
- added python3-devel package (needed for some of the Python requirements)
and install python3 instead of a fixed python38
Tested on a vanilla Fedora 39 Docker image.
Signed-off-by: Benjamin Cabé <benjamin@zephyrproject.org>