Fix Linux builds and upgrade CEF

[cadivus]

Hi!

On Ubuntu 24.04, builds fail (see build_errors.txt).

This is my toolchain:

$ gcc --version
gcc (Ubuntu 12.3.0-17ubuntu1) 12.3.0
Copyright (C) 2022 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

$ g++ --version
g++ (Ubuntu 12.3.0-17ubuntu1) 12.3.0
Copyright (C) 2022 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

$ clang --version
Ubuntu clang version 18.1.3 (1ubuntu1)
Target: x86_64-pc-linux-gnu
Thread model: posix
InstalledDir: /usr/bin
$ g++ --version
g++ (Ubuntu 12.3.0-17ubuntu1) 12.3.0
Copyright (C) 2022 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

$ cmake --version
cmake version 3.28.3

CMake suite maintained and supported by Kitware (kitware.com/cmake).

This PR fixes that and upgrades CEF by using offical builds (https://github.com/chromiumembedded/cef?tab=readme-ov-file#quick-links).