Update `mocha` and `request` dependencies.

Change-Id: Ic0ee7db28b0dc45edd5c273747c80df7e8a0917b
Add --no-compat option to avoid pediapress compatibility overhead.

Using the `--no-compat` option avoids resource fetches and bundle bloat
which are used only for pediapress compatibility, not by any of the
modern backends.

Change-Id: I520837b0fdf838df405361bda2bfbf7507f7ac01