Update Captions in the API reference

[szekelyzol]

Changes are for this Asana task.

Summary:

• Updated the description for the language parameter across all captions endpoints' request schemas
• Updated the code snippets where the language parameter is explained
• Updated the response schemas for all captions endpoints to contain the new languageName field
• Added 400 response schemas and response examples to all captions endpoints
• Added languageName to all example responses across captions endpoints
• Added descriptions to the caption response object schema

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  • https://app.asana.com/0/0/1206003116770301