optimism: `fee too low` error on Truffle migration or test when using ops tool

Describe the bug Users in Discord reported errors when using Kovan AND the ops tool. Running Truffle tests results in a fee too low error.

Error: while migrating ERC20: fee too low: 100829625000000, 
use at least tx.gasLimit = 54181975 and tx.gasPrice = 15000000

Note that this error is after hardcoding a gasLimit and gasPrice that matches the error log’s suggestion (also, based on user reports, I had different suggested values than those reported).

To Reproduce Steps to reproduce the behavior:

1. git clone https://github.com/ethereum-optimism/optimism.git
2. Pull recent changes from develop branch: git pull origin develop
3. Start docker services: yarn && yarn build && cd ops && docker-compose build && docker-compose up
4. In a new terminal, run Truffle tests under optimism/examples/truffle: yarn truffle test --network optimism --config truffle-config-ovm.js
5. See error:

Error: while migrating ERC20: fee too low: 100829625000000, 
use at least tx.gasLimit = 54181975 and tx.gasPrice = 15000000

Expected behavior Tests should pass after adding the suggested gasLimit and gasPrice values

System Specs:

• OS: MacOS
• Latest commit of develop branch