warning: unused `std::result::Result` that must be used
  --> mfm_machine/src/state_machine/mod.rs:81:9
   |
81 | /         tracker.track(
82 | |             Index::new(state_index, state.label(), state.tags()),
83 | |             context.clone(),
84 | |         );
   | |_________^
   |
   = note: this `Result` may be an `Err` variant, which should be handled
   = note: `#[warn(unused_must_use)]` on by default
help: use `let _ = ...` to ignore the resulting value
   |
81 |         let _ = tracker.track(
   |         +++++++