Simplify division by zero (division by one / multiplication by zero / multiplication by one) for Decimal types as well

[alamb]

@HaoYang670 added the simplification rule to simplify col * 0 for numeric types other than Decimal in #3627

This ticket tracks adding this support for Decimal.

Originally posted by @HaoYang670 in #3627 (comment)

[alamb]

Marking as a good first issue as the pattern exists for other types, so a contributor could follow the existing pattern and get a little familiar with the code