test: remove bluebird remnants from test fixture

The test fixture in test/fixtures/bluebird was largely copied from
bluebird, where a regression in Node.js was discovered. Simplify the
test by removing a lot of things that aren't necessary to replicate the
problem. Change name from bluebird to something less likely to cause
someone to believe that we are actually loading bluebird (as we are
not).

PR-URL: https://github.com/nodejs/node/pull/31435


Reviewed-By: Richard Lau <riclau@uk.ibm.com>
Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>
Reviewed-By: David Carlier <devnexen@gmail.com>