Fix test and move examples to proper place

rust/tests/chatroom.rs → rust/examples/chatroom.rs

@@ -316,3 +316,5 @@ pub mod dependency_2 {
         }
     }
 }
+
+fn main() {}

rust/tests/contract_components.rs → rust/examples/contract_components.rs

@@ -367,3 +367,5 @@ mod children {
         }
     }
 }
+
+fn main() {}

rust/tests/typed_contract.rs → rust/examples/typed_contract.rs

@@ -79,3 +79,5 @@ impl TypedContract for Contract {
         unimplemented!()
     }
 }
+
+fn main() {}

rust/src/contract_interface.rs

@@ -1307,9 +1307,7 @@ impl TryInto<Vec<u8>> for WrappedContract {
 
 impl Display for WrappedContract {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
-        write!(f, "Contract(")?;
-        self.key.fmt(f)?;
-        write!(f, ")")
+        self.key.fmt(f)
     }
 }