Implement std::fmt::Display for Query

[slvrtrn]

It might be helpful to log the queries.
Currently, it is not possible:

error[E0277]: `Query` doesn't implement `std::fmt::Display`
  |
8 |     println!("{query}");
  |               ^^^^^^^ `Query` cannot be formatted with the default formatter
  |
  = help: the trait `std::fmt::Display` is not implemented for `Query`

The current implementation of SQLBuilder moves mut self, so it looks like some refactoring will be required there.