Update to handle recent changes to casper-node

This PR includes a few small changes to match recent updates to casper-node's dev branch.

updates the pinned Rust version to nightly-2022-08-03
removes usage of deprecated DEFAULT_RUN_GENESIS_REQUEST from generated tests
updates this crate's test to invoke a generated project's make test with the env var RUSTFLAGS="-D warnings" set
fixes new clippy warnings

casper-ecosystem / cargo-casper