Allow custom eta range in material map validation, requires ACTS 36.1

[ShujieL]

The material validation script has a hard-coded eta range of -4 to 4. It will only impact the validation plots, the generated map will follow the material recording range (default is -8 to 8 in ePIC).

It's possible to customize the range by changing https://github.com/acts-project/acts/blame/d19a6d75ad5df23f45aaa776b0129137ba941d38/Examples/Scripts/Python/material_validation.py#L39 in ACTS V36.1, so that we can see the map v.s. geantino comparison at far-forward region. It's not critical. We can re-visit after the relevant ACTS version is ready.

[ShujieL]

We still need to update the ACTS script to allow custom range