This updates the tests to version 0.11 of the wasi bindings. There aren't any fundamental changes here; this just syncs up with the latest version so that it's consistent with other users of the wasi APIs.
This is the test-programs crate, which builds and runs whole programs
compiled to wasm32-wasi.
To actually run these tests, the test-programs feature must be enabled, e.g.:
cargo test --features test-programs/test_programs --package test-programs