fix some markdown error

Author: NathanSWard

examples/README.md

@@ -150,7 +150,7 @@ Example | File | Description
 --- | --- | ---
 `ecs_guide` | [`ecs/ecs_guide.rs`](./ecs/ecs_guide.rs) | Full guide to Bevy's ECS
 `change_detection` | [`ecs/change_detection.rs`](./ecs/change_detection.rs) | Change detection on components
-`command_error_handling` | [`ecs/command_error_handling.rs](./ecs/command_error_handling.rs) | Error handling fallible commands
+`command_error_handling` | [`ecs/command_error_handling.rs`](./ecs/command_error_handling.rs) | Error handling fallible commands
 `event` | [`ecs/event.rs`](./ecs/event.rs) | Illustrates event creation, activation, and reception
 `fixed_timestep` | [`ecs/fixed_timestep.rs`](./ecs/fixed_timestep.rs) | Shows how to create systems that run every fixed timestep, rather than every tick
 `hierarchy` | [`ecs/hierarchy.rs`](./ecs/hierarchy.rs) | Creates a hierarchy of parents and children entities