ci: Use distro packaged clang-tidy headers in Fedora base image
Since !7628 (merged), Fedora has added the clang-tools-extra-devel
package.
While at it, add nlohmann-json to the Fedora base image in preparation for !8341 (closed). We need version 3.11.2 or higher, which Debian 10 does not package, so leave it out of the Debian base images.