Regenerate azure-search-documents with JsonSerializable code sharing

[alzimmermsft]

Description

Enables the Autorest configuration where JsonSerializable classes in a polymorphic hierarchy will share common serialization code.

All SDK Contribution checklist:

• The pull request does not introduce [breaking changes]
• CHANGELOG is updated for new features, bug fixes or other significant changes.
• I have read the contribution guidelines.

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• Pull request includes test coverage for the included changes.

[azure-sdk]

API change check

APIView has identified API level changes in this PR and created following API reviews.

com.azure:azure-search-documents