PINN solver benchmarks are broken

[killah-t-cell]

Parts of the PINN solver benchmarks are not compiling

https://benchmarks.sciml.ai/html/PINNErrorsVsTime/allen_cahn_et.html

[ChrisRackauckas]

Yes, I pinged @KirillZubov and @francescocalisto on fixing it, though if anyone wants to get to it first be my guest because I don't plan to get to it any time soon. I was just trying to get the benchmarks like 90% setup so that others can then help 😅

[KirillZubov]

look like just outdated code after update and it is just need add couple new parameter to build_loss_function.

[KirillZubov]

https://github.com/SciML/SciMLBenchmarks.jl/pull/355

I fixed allen_cahn. Not sure about the results of the prediction.

@francescocalisto could you please check how much iteration is needed and etc.

Also, other scripts in PINNErrorsVsTime need to update because there also use low-level API which was changed, and code outdate. https://github.com/SciML/SciMLBenchmarks.jl/tree/master/benchmarks/PINNErrorsVsTime

[ChrisRackauckas]

This is fixed.