Remove unused import of micro simulations

[tjwsch]

This removes an unnecessary import of the MicroSimulation class that was not used. In a personal meeting, we also discussed if one of the logger level sets could be removed but on further investigation, they seem to serve slightly different purposes.

[IshaanDesai]

Can you also please remove the other lines that we discussed? Good to do more than one cleanups in one PR.

[tjwsch]

After further investigation on the other lines, I found that setting the logger level in the root logger and a handler serves different purposes, thus both setLevel calls are necessary, as I wrote in my first comment. That was the only other cleanup I remember us discussing.