[Rust] Boolean AND/OR kernels should follow sql behaviour regarding null values

The AND/OR boolean kernels currently have the same null handling as other binary expressions, if either the left or right input is NULL then the result will be NULL. The standard sql behaviour is different:

OR: If one input is TRUE then the result will be TRUE even if the other input is NULL

AND: If one input is FALSE then the result will be FALSE regardless of the other input

This behaviour makes sense if you think of NULL as meaning UNKNOWN.