Eliminate Unsatisfiable Boolean Expressions

**Is your feature request related to a problem or challenge? Please describe what you are trying to do.**

I noticed Datafusion is not able to simplify the expression

```
A ^ !A
```

Whilst it is unlikely for a user to write such an expression, it is not uncommon for boolean expressions to reduce to something unsatisfiable. Where this is the case, substituting in `false` may allow for further simplification.

**Describe the solution you'd like**

It would be awesome if Datafusion was able to detect and eliminate unsatisfiable boolean expressions. I believe this is an NP-hard problem in the general case, but should be tractable for a low number of variables.

The issue does not name specific files or tests; first locate DataFusion's boolean-expression simplification entry point and trace how `A ^ !A` is handled. Check the existing simplification tests, then define how unsatisfiable expressions should be detected and replaced with `false`, including the expected behavior for a small number of variables.

Written by the indexing model from the issue text.