[feature-wip](Nereids) Add scalar function code generator and some function trait

[924060929]

Proposed changes

This pr did these things:

1. Change the nullable mode of 'from_unixtime' and 'parse_url' from DEPEND_ON_ARGUMENT to ALWAYS_NULLABLE, which nullable configuration was missing previously.
2. Add some new interfaces for origin NullableMode. This change inspired by the grammar of scala's mix-in trait, It help us to quickly understand the traits of function without read the lengthy procedural code and save the work to write some template code, like class Substring extends ScalarFunction implements ImplicitCastInputTypes, PropagateNullable. These are the interfaces:
   • PropagateNullable: equals to NullableMode.DEPEND_ON_ARGUMENT
   • AlwaysNullable: equals to NullableMode.ALWAYS_NULLABLE
   • AlwaysNotNullable: equals to NullableMode.ALWAYS_NOT_NULLABLE
   • others ComputeNullable: equals to NullableMode.CUSTOM
3. Add GenerateScalarFunction to generate nereids-style function code from legacy functions, but not actual generate any new function class yet, because the function's trait is not ready for use. I need add some traits for the legacy function's CompareMode and NonDeterministic, this thought is the same as ComputeNullable.

Checklist(Required)

1. Does it affect the original behavior:
   • Yes
   • No
   • I don't know
2. Has unit tests been added:
   • Yes
   • No
   • No Need
3. Has document been added or modified:
   • Yes
   • No
   • No Need
4. Does it need to update dependencies:
   • Yes
   • No
5. Are there any changes that cannot be rolled back:
   • Yes (If Yes, please explain WHY)
   • No