chore: remove hifld from list of supported model

[rouille]

Pull Request doc

Purpose

Remove hifld from list of supported models since we will likely merge the hifld branch into develop before we have the HIFLD grid model ready.

What the code is doing

If a user tries to instantiate the Grid class with the source parameter set to hifld a ValueError will be raised. Also, the set_grid method of the Create class will throw the same error.

Testing

>>> from powersimdata import Grid
>>> g = Grid("ERCOT", source="hifld")
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/Users/brdo/CEM/PowerSimData/powersimdata/input/grid.py", line 35, in __init__
    raise ValueError(
ValueError: Source must be one of usa_tamu or the path to a .mat file that represents a grid 

Where to look

The powersimdata.input.grid module

Usage Example/Visuals

N/A

Time estimate

2min

[BainanXia]

Make sense