Can't differentiate boundscheck expression $(Expr(:boundscheck)).

We are getting this error in CI on Julia nightly ```julia Test threw exception Expression: !(isnothing(Zygote.gradient(diff_loss, ps))) Can't differentiate boundscheck expression $(Expr(:boundscheck)). You might want to check the Zygote limitations documentation. https://fluxml.ai/Zygote.jl/latest/limitations ``` ref https://github.com/impICNF/ContinuousNormalizingFlows.jl/actions/runs/6318051623/job/17157645401#step:5:561