Optimization for CASE WHEN for protecting against divide by zero

[irenjj]

Which issue does this PR close?

closes https://github.com/apache/datafusion/issues/11570

Rationale for this change

What changes are included in this PR?

Add an optimization opration for case like:

CASE WHEN y > 0 THEN x / y ELSE null END

Simplify the check by div_checked.

Are these changes tested?

Are there any user-facing changes?