* Update ubuntu-latest tag to ubuntu-22.04
Everytime a CI service such a GitHub actions update the images
corresponding to their 'latest' tags, pipelines tend to have some
hipcups due to changes in the distribution default packages.
By fixing the images to a specific one, we should be more resilient to
changes in the Github actions environment.
* Use same build directory used in CMake presets
Additional interesting changes in this commit:
- conan: use cmake-conan for better CMake-Conan integration
- cmake+doc: Remove deprecated EXIV2_ENABLE_WIN_UNICODE
- Ignore CMakeUserPresets.json
- doc: Add notes about the usage of CMake presets