Remove -c http.sslverify=false from all git clones
(enables proper TLS verification, closes MITM risk).
Explicitly install ca-certificates in every CI Docker image.
Split functional tests into 4 parallel groups and add check-functional-parallel target (~3x faster CI runs).
Add branch-aware LCOV coverage reporting with new --enable-coverage option and lcov summary in CI pipeline.
Enable ccache via -C configure flag for faster recompilations.
Install lcov in all Docker images and use --depth 1 git clones + parallel make -j$(nproc) for quicker container builds.
Update CONTRIBUTING.md with instructions for parallel test groups and adding new ones.
All changes are tightly related CI/performance improvements developed in sequence. No external service uploads (e.g. Codecov skipped due to Gitea incompatibility).
- Add TERM=xterm-256color for PTY support in functional tests
- Disable SSL verification for git clone in restricted networks
- Add error handling for Arch reflector installation
* Also pass `$*` to `configure` when invoking `ci-build.sh`, so one can
e.g. run `./ci-build.sh --without-xscreensaver`
Signed-off-by: Steffen Jaeckel <s@jaeckel.eu>
