Fix lint warning

Fixing lint warning lagged in CI
<https://github.com/nextstrain/auspice/actions/runs/10689100704/job/29630462669#step:5:11>

src/reducers/tree.js

@@ -66,11 +66,11 @@ const Tree = (state = getDefaultTreeState(), action) => {
       });
     case types.TREE_TOO_DATA:
       return action.tree;
-    case types.ADD_EXTRA_METADATA:
+    case types.ADD_EXTRA_METADATA: {
       // add data into `nodes` in-place, so no redux update will be triggered if you only listen to `nodes`
       addNodeAttrs(state.nodes, action.newNodeAttrs);
       // add the new nodeAttrKeys to ensure tip labels get updated
-      const { nodeAttrKeys } = processNodes(state.nodes)
+      const { nodeAttrKeys } = processNodes(state.nodes);
       // add the new colorings to totalStateCounts so that they can function as filters
       return {
         ...state,
@@ -80,6 +80,7 @@ const Tree = (state = getDefaultTreeState(), action) => {
         },
         nodeAttrKeys
       };
+    }
     default:
       return state;
   }