Remove deprecated mongooplog tool

The mongooplog tool was deprecated in 3.2. pasette has indicated that it can be removed for the 3.6 cycle.

I'll open a TOOLS ticket to remove it from the tools repo, but before that happens, we need to make sure that nothing in the server build/test process that depends on it will be affected by such a change.

This will also require a documentation change to note the removal in the release notes.