Merge pull request OffchainLabs#1895 from OffchainLabs/signal-snapshot

Save database checkpoint on SIGUSR1

edits on useful addresses

suppress known memory leak during test run as well

Clang tidy performance optimizations

add l1 rpc url env var to deploy instructions; add check in instantia…

…te bridge

Rollback to older docker base

Rollback to older docker base

Rollback to older docker base

Rollback to older docker base

Rollback to older docker base