install necessary cmake version directly from cmake github releases

[bablokb]

ESP-IDF needs a more recent cmake version than the current base system in Github-codespaces provides. Adding the Kitware repo does not help anymore since the cmake version there is also outdated.

This PR therefore installs a suitable cmake version directly from the Github releases of cmake.

[dhalbert]

This seems fine! I looked in esp-idf and the minimum CMake version looks like 3.19.0 now, but the minimums vary among components. That's the highest version requested now that I see.

If you just did apt install cmake would that do fine? I don't know how a devcontainer is set up so that may not make sense?

[bablokb]

The devcontainer is basically a docker image running Ubuntu. cmake is already installed, but the highest version is 3.16. Maybe there are some backport repos with newer versions that could be added/activated, but that seems more complicated than this solution. And after all, devcontainers are throw-away environments, so installing to /usr/local should be fine.

[dhalbert]

@bablokb Got it, thanks. I have already advanced to Ubuntu 26.04, which has cmake 4.something, but that may not be available.