FLoops.jl is now incompatible with Transducers.jl

[simsurace]

FLoops.jl is stuck at 0.3 for BangBang.jl compat, and Transducers.jl requires 0.4.
This probably means that FLoops.jl needs to be migrated to JuliaFolds2 as well.

[CarloLucibello]

Would it be possible to fork FLoops and update its compatibility with BangBang's latest release? We are using it in MLUtils's DataLoader which is widely used by the deep learning ecosystem. Switching the DataLoader to another backend may be challenging at the moment JuliaML/MLUtils.jl#175