Forks have been removed in cocotb

[toddstrader]

But cocotb-bus still uses them:

cocotb-bus/src/cocotb_bus/drivers/__init__.py

Line 48 in 2c846dc

self._cr = cocotb.fork(self._cr_twiddler(generator=generator))

cocotb-bus does seem to understand it can't tolerate cocotb 2.0:

cocotb-bus/setup.py

Line 33 in 2c846dc

"cocotb>=1.5.0.dev,<2.0"

but it is now not possible to run HEAD-to-HEAD.

For reference:
cocotb/cocotb#3425