various improvements

[EvanBldy]

Problem

• Some requirements are outdated.
• Refactoring on event_stream is needed + there's an error sometimes : ERROR in event_stream: set_application_routes..disconnected() takes 0 positional arguments but 1 was given
• There's no route to batch comments for different tasks.
• There's an error when parsing fps from a preview file ("ValueError: could not convert string to float: ''"") when entity["data"]["fps"] is an empty string.

Solution

• Upgrade outdated requirements.
• Refactoring for event_stream + fix error.
• Add new route to batch comments for different tasks : "/actions/tasks/batch-comment" + refactoring.
• Fix error when parsing fps from a preview file : ignore empty string in entity["data"]["fps"].