New run_opt_neutral function

[TristanSJones]

• Mutch like the torsional function it needs to be adapted to make this new function that takes the updated geometry from the torsional parser and uses it in the input file. (done with the cclib parser

https://github.com/matta-research-group/auto_workflow/blob/b2825f30424edf3f85d70397308c5a926d252b54/torsion.py#L7