Add an imprint on the end of any release message, and show a template in the
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Integrated the new `hardhat-ledger` support for controlling its UI display. Ignition now takes control of displaying the messages from the ledger (e.g. "Connect wallet").

Fixes #720

Add a config option for `maxPriorityFeePerGas`, to allow the user to override
the internal Ignition heuristic.

Resolves #728

Before falling back to the default max priority fee (currently 1gwei) attempt
to call `eth_maxPriorityFeePerGas` as an RPC call and use that if available.

If the user has set a `maxPriorityFeePerGas` in config, that takes priority over
the RPC call.

Resolves #743

Private chains like besu can be run in a zero gas fee mode. We support this by
altering the gas fee calculation to detect whether we are on such a chain and
return zeroed values.

Update the packages versions and changelogs for the `0.15.2 -
2024-05-02` release.