example of functions for alias

### Contributions

- [x] I have read the contribution docs, and understand what's expected of me.

### Link to the page on docs.getdbt.com requiring updates

https://docs.getdbt.com/reference/resource-configs/alias

### What part(s) of the page would you like to see updated?

we show examples for configuring `alias` for models, seeds, snapshots, and tests.

we should add an example for functions as well.

we should do the same for config pages for other "general" configs that you can apply to functions -> https://docs.getdbt.com/reference/function-configs

### Additional information

_No response_