Support Rust UDF

[yongda-fan]

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Currently Ballista does not support rust UDF, which makes it hard to process data using some custom function or with external libraries.

Describe the solution you'd like
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There are two possible Solutions

Register the UDF directly

We load rust dynamic library into the executor (similar to this PR: apache/datafusion#1881, and we have partial code here https://github.com/apache/arrow-ballista/tree/main/ballista/core/src/plugin) and register the UDF directly to the DataFusion.

issues:

1. rust has never guaranteed a stable ABI (i.e. memory layout), therefor the fields in the UDF class in the plugin maybe interpreted incorrectly, e.g. ColumnarValue or Signature, etc.
2. in practice same rustc version + same optimization level gives the same ABI (i.e. memory layout for the class). this suggest the plugin must be complied with the exact same rustc and compiler flags.
3. or alternatively we could use a stable api library such as abi_stable or stabby marks all UDF related class

Reconstruct a UDF function a function with Arrow data as parameter and Arrow data as return type

we can only load a function that use Arrow data as parameter and returns, since this is memory layout stable (e.g. using https://arrow.apache.org/rust/arrow/ffi/struct.FFI_ArrowArray.html). we could pass the signature using a serialized string or something.

similar to this: https://github.com/apache/arrow-datafusion-python/blob/main/src/udf.rs

issues:

1. we lost lots of flexibility provided by rust ScalarUdfImpl, such as change the signature by value, or provide specialized code path to use the ColumnarValue::Scalar

Describe alternatives you've considered
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alternatively, we could build a custom ballista executor each time we want to add or modify a UDF and deploy it.

Additional context
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