Explicitly include equipment as a "Tech Squares resource" in safer dances policy

[dehnert]

The Safer Dances Policy notes:

This policy applies to all Tech Squares events, defined as not only our regular Tuesday and Saturday dances but also all other events using Tech Squares resources, such as rooms reserved through Tech Squares.

We should add "and Tech Squares equipment", because it seems like clearly one of our resources, and it comes up relatively often.