include optional impact drill to "How to build a PAPRa Fan Box (96mm)"

[Connect Filter Interface to Fan Box Assembly](https://tetrabiodistributed.github.io/papra/v1.1/fan-box/#_connect_filter_interface_to_fan_box_assembly) step includes option to use impact drill - should be listed as an optional tool under [recommended tools](https://tetrabiodistributed.github.io/papra/v1.1/fan-box/#_recommended_tools)