Add setSerializer to Component\Serialization\Yaml and deprecate Core\Serialization\Yaml

Waiting to get feedback on the general idea before adjusting the approach in the MR.

The Needs Review Queue Bot → tested this issue. It no longer applies to Drupal core. Therefore, this issue status is now "Needs work".

This does not mean that the patch needs to be re-rolled or the MR rebased. Read the Issue Summary, the issue tags and the latest discussion here to determine what needs to be done.

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