Implement Aliases for ScalarUDF

[alamb]

Is your feature request related to a problem or challenge?

As part of #8045 we need to ensure that scalar UDFs have the same functionality as built in functions.

One gap that currently exists is "aliases".

For example, pow and power are both resolved to the same function.

Describe the solution you'd like

Implement aliasing for ScalarUDF

Basically :

1. Add aliasing to ScalarUDF API
2. Hook it up so that ScalarUDF can accept aliases and that the planner can use them
3. Write an end to end test (probably in https://github.com/apache/arrow-datafusion/blob/32fe1761287c9b58294a54805a0fcafc4ab046b8/datafusion/core/tests/user_defined/user_defined_scalar_functions.rs#L1-L0)

I am envisioning creating a scalar UDF with a new function with_alias. Something like

ScalarUDF::new(
        "pow",
        &Signature::exact(input_types, volatility),
        &return_type,
        &fun,
    )
   .with_alias("power")

Currently the alias list is here:
https://github.com/apache/arrow-datafusion/blob/094a0e2d0c8c1f71c985c7bfdf21433ebc8f203e/datafusion/expr/src/built_in_function.rs#L1374

Describe alternatives you've considered

No response

Additional context

No response

[Veeupup]

hi @alamb maybe I can help with this ticket

[edmondop]

hi @alamb maybe I can help with this ticket

@Veeupup if you decide not to proceed I will pick this up, let me know

Ed

[Veeupup]

@edmondop hi! very glad to have you there!

I have made a PR #8360 hours ago. Maybe you can help me review it and let's make it better together! : )