feat: add traits5.rs exercise

exercises/traits/traits5.rs

@@ -0,0 +1,31 @@
+// traits5.rs
+//
+// Your task is to replace the '??' sections so the code compiles.
+// Don't change any line other than 27.
+
+// I AM NOT DONE
+
+pub trait SomeTrait {
+    fn some_function(&self) -> bool {
+        true
+    }
+}
+
+pub trait OtherTrait {
+    fn other_function(&self) -> bool {
+        true
+    }
+}
+
+struct SomeStruct {
+    name: String,
+}
+
+impl SomeTrait for SomeStruct {}
+impl OtherTrait for SomeStruct {}
+
+fn some_func(item: ??) -> bool {
+    item.some_function() && item.other_function()
+}
+
+fn main() {}