Bump ethereumex from 0.14.0 to 0.15.0 - #278

The strategy configuration was canceled because "test._28_x_1_20_false" failed

Process completed with exit code 2.

test create_access_list/2 returns the node error when the simulated transaction reverts (EthersTest)

test maybe_add_gas_limit adds gas limit to the transaction params (Ethers.UtilsTest)

Node.js 20 is deprecated. The following actions target Node.js 20 but are being forced to run on Node.js 24: actions/cache@v3, actions/checkout@v3. For more information see: https://github.blog/changelog/2025-09-19-deprecation-of-node-20-on-github-actions-runners/