Re-enable SSE usage aggregation recurring task

[gagantrivedi]

Description
SSE usage data aggregation was previously disabled due to a bug in the task processor:
Flagsmith/flagsmith-common@c0b8dde

We need to re-enable the aggregation task, migrate the currently accumulated data and clean up the existing bucket

Tasks

• Re-enable the SSE usage aggregation task
• Move existing SSE usage data to a new bucket
• Clean up the current bucket