## Description 

bridge e2e tests can't use sim tests today because of several reasons.
With `tokio::test` we stumble into a case where high commit rate (50ms)
can cause reconfiguration to take long and eventually build up the
checkpoint queue (interesting it is the checkpoint content downloading
queue). This PR introduces an env var to keep the commit rate normal.

## Test plan 

How did you test the new or updated feature?

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## Release notes

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any actions they must take to implement updates.

- [ ] Protocol: 
- [ ] Nodes (Validators and Full nodes): 
- [ ] Indexer: 
- [ ] JSON-RPC: 
- [ ] GraphQL: 
- [ ] CLI: 
- [ ] Rust SDK: