GO-4886: add joinSpace param in PublishState pb model

[AnastasiaShemyakinskaya]

1. Save joinSpace in Version field for server
2. Add new parameter in middleware pb model PublishingState
3. Retrieve joinSpace parameter from version and save it in pb model for client

[github-actions]

Previous Coverage	50.6% of statements
New Coverage	50.6% of statements
Patch Coverage	80.0% of changed statements (16/20)

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