report the presence of pending tests

I find it helpful to see if there are pending (not yet implemented) tests and, if so, which.

If no test fails and there are pending tests, tabs will be rendered yellow, and the names of those tests (also in yellow) will be listed inside the log panel.

Unfortunately this currently only works with Buster and Mocha because they actually report pending tests.
Jasmine does not report any pending tests but rather excludes them entirely from the run.
And QUnit has no notion of pending tests at all.