Release v0.2.4

What's Changed

• Add threshold-in-hours to config instead of hard code. by @ping-ke in #439
• Dashboard: Load mined event from DB instead of refetch again from chain. by @ping-ke in #437
• Translate error message from calling contract by @syntrust in #438
• fix custom error selector by @ping-ke in #440
• Reorganized flags: remove rollup config and network flag by @ping-ke in #441
• Improvements on scripts and email, etc. by @syntrust in #442
• Remove Docker compose, etc. by @syntrust in #445
• mainnet scripts by @syntrust in #444
• remove rpc by @syntrust in #446
• Mainnet deployment by @qzhodl in #448
• Fix contract doesn't exist but still returns incorrect value by @ping-ke in #449
• bump version by @syntrust in #450

Full Changelog: v0.2.3...v0.2.4