Add test coverage of all unsafe code

[rcoh]

• https://duchess-rs.github.io/duchess/coverage/coverage/home/runner/work/duchess/duchess/src/raw.rs.html#L27
• https://duchess-rs.github.io/duchess/coverage/coverage/home/runner/work/duchess/duchess/src/raw.rs.html#L502
• https://duchess-rs.github.io/duchess/coverage/coverage/home/runner/work/duchess/duchess/src/cast.rs.html#L44
• https://duchess-rs.github.io/duchess/coverage/coverage/home/runner/work/duchess/duchess/src/cast.rs.html#L105
• https://duchess-rs.github.io/duchess/coverage/coverage/home/runner/work/duchess/duchess/src/jvm.rs.html#L143
• https://duchess-rs.github.io/duchess/coverage/coverage/home/runner/work/duchess/duchess/src/jvm.rs.html#L182
• https://duchess-rs.github.io/duchess/coverage/coverage/home/runner/work/duchess/duchess/src/jvm.rs.html#L388
• https://duchess-rs.github.io/duchess/coverage/coverage/home/runner/work/duchess/duchess/src/jvm.rs.html#L505
• https://duchess-rs.github.io/duchess/coverage/coverage/home/runner/work/duchess/duchess/src/jvm.rs.html#L518
• https://duchess-rs.github.io/duchess/coverage/coverage/home/runner/work/duchess/duchess/src/array.rs.html#L24
• https://duchess-rs.github.io/duchess/coverage/coverage/home/runner/work/duchess/duchess/src/array.rs.html#L44
• https://duchess-rs.github.io/duchess/coverage/coverage/home/runner/work/duchess/duchess/src/ref_.rs.html#L60
• https://duchess-rs.github.io/duchess/coverage/coverage/home/runner/work/duchess/duchess/src/ref_.rs.html#L132
• https://duchess-rs.github.io/duchess/coverage/coverage/home/runner/work/duchess/duchess/src/ref_.rs.html#L181
• https://duchess-rs.github.io/duchess/coverage/coverage/home/runner/work/duchess/duchess/src/ref_.rs.html#L203

This doesn't cover unsafe code generated by the macro—We need figure out how we want to capture that being tested.