We no longer need to merge pages this way. Much of the functionality
was there to implement page splitting without hitting ulimit which
will be fixed in qpdf > 8.0.2. The tests were expensive to run.
Also remove pytest-timeout since it breaks the Linux build.
qpdf from appimage does not report its version with --version if renamed
or accessed via symlink. Use an environment variable to supply it
where needed.
James R. Barlow