Resolve semicolon_if_nothing_returned pedantic clippy lint

    error: consider adding a `;` to the last statement for consistent formatting
       --> src/map.rs:309:9
        |
    309 |         self.map.clone_from(&source.map)
        |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: add a `;` here: `self.map.clone_from(&source.map);`
        |
        = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#semicolon_if_nothing_returned
        = note: `-D clippy::semicolon-if-nothing-returned` implied by `-D clippy::pedantic`

Author: dtolnay

src/map.rs

@@ -306,7 +306,7 @@ impl Clone for Map<String, Value> {
 
     #[inline]
     fn clone_from(&mut self, source: &Self) {
-        self.map.clone_from(&source.map)
+        self.map.clone_from(&source.map);
     }
 }