Updated MLPCpp module supporting additional input/output scaling methods

[EvertBunschoten]

Proposed Changes

Updated the MLPCpp submodule which is now able to use different scaling methods (standard, robust, and min-max) for scaling the neural network inputs and outputs.

Related Work

This update relates to the parts of SU2 regarding data-driven simulations (CDataDrivenFluid and CFlameletFluid).

PR Checklist

• I am submitting my contribution to the develop branch.
• My contribution generates no new compiler warnings (try with --warnlevel=3 when using meson).
• My contribution is commented and consistent with SU2 style (https://su2code.github.io/docs_v7/Style-Guide/).
• I used the pre-commit hook to prevent dirty commits and used pre-commit run --all to format old commits.
• I have added a test case that demonstrates my contribution, if necessary.
• I have updated appropriate documentation (Tutorials, Docs Page, config_template.cpp), if necessary.

[joshkellyjak]

Maybe a good oppurtunity to correct this issue?

#2366

[EvertBunschoten]

Maybe a good oppurtunity to correct this issue?

#2366

I swapped the descriptions so once this PR is closed we can close the issue as well.

[bigfooted]

LGTM