Fix cmap unittests

When the binary CMaps were added, some of the relevant unit tests were not changed. This patch updates them, so that we actually test the current implementation.
What's somewhat troubling here is that we currently have CMap unit tests that passes, *despite* not working as intended (the CMap files doesn't load).

In this PR I'm also removing the remaining references to cidmaps.js, which I missed in #5088.