ALE adapter round-trip CDL Values

## Feature Request

New feature

## Description

The ALE adapter reads CDL values into the `cdl` namespaces of clip metadata dictionaries from the `ASC_SAT` and `ASC_SOP` fields, however it does not write them back out. It would be helpful to have the ALE adapter round-trip this data. This would also match the EDL adapter behavior.

## Context

For how the adapter reads CDL values, look [here](https://github.com/PixarAnimationStudios/OpenTimelineIO/blob/6ce63ff7bdb5b90f66aa090d5689f566ca7b5b33/contrib/opentimelineio_contrib/adapters/ale.py#L123-L157).
For an example of how the EDL adapter writes out this metadata, look [here](https://github.com/PixarAnimationStudios/OpenTimelineIO/blob/6ce63ff7bdb5b90f66aa090d5689f566ca7b5b33/src/py-opentimelineio/opentimelineio/adapters/cmx_3600.py#L1348-L1368)