Create a new safe divide cross db macro

[graciegoheen]

Describe the feature

I want to add a "safe divide" cross db macro (like DIV0 in snowflake) to prevent errors when dividing by 0.

Describe alternatives you've considered

Additional context

Who will this benefit?

Package developers - we're currently using nullif() on the denominator in dbt_project_evaluator package and would like to replace this with a simple safe divide macro.

Are you interested in contributing this feature?

Yes. I, @angelica-lastra, and @deanna-minnick will be collaborating on this!

[joellabes]

We talked about this internally - excited to see it come together!