Fix for checkpoint issue

[andygolay]

Security Fix: Add Checkpoint in release_rate_limit_capacity

• Fix for issue 1 in https://www.notion.so/movementlabs/OFT-issues-2ae18675b2d780af9013ee9082afccdd
• Add checkpoint before modifying in_flight_on_last_update in release_rate_limit_capacity to account for decay, preventing loss of decay information and potential rate limit bypass exploits
• Fixes issue where multiple releases in quick succession could use outdated in_flight_on_last_update values, matching the pattern used in try_consume_rate_limit_capacity_at_time