Releasing Gammu

1. Ensure that all tests pass on both Linux and Windows.

2. Update the version in CMakeLists.txt, gammu.spec, and description-pak. Update ChangeLog with the release date and changes since the previous release.

3. Update man pages using make update-man.

4. Configure and verify the source package with cmake -S . -B _build -DCMAKE_BUILD_TYPE=Release and cmake --build _build --target package_source.

5. (Optional) Test the created source packages.

6. Commit the release changes, create a tag matching the version, and push the commit and tag to GitHub. The release workflow builds the source packages and Windows installers and publishes the GitHub release from the tag.

7. Import the release to the website.