feat: set strict mode

Author: kotarella1110

react-app/src/bootstrap.tsx

@@ -1,5 +1,10 @@
 import App from "./App";
-import React from "react";
+import { StrictMode } from "react";
 import ReactDOM from "react-dom";
 
-ReactDOM.render(<App />, document.getElementById("root"));
+ReactDOM.render(
+  <StrictMode>
+    <App />
+  </StrictMode>,
+  document.getElementById("root")
+);

shell/src/apps/NavBar.tsx

@@ -4,20 +4,22 @@ import singleSpaReact from "single-spa-react";
 import { navigateToUrl } from "single-spa";
 
 export const NavBar = () => (
-  <nav>
-    <ul style={{ display: "flex", listStyle: "none", margin: 0, padding: 0 }}>
-      <li style={{ padding: "8px" }}>
-        <a href="/" onClick={navigateToUrl}>
-          Home
-        </a>
-      </li>
-      <li style={{ padding: "8px" }}>
-        <a href="/react" onClick={navigateToUrl}>
-          React
-        </a>
-      </li>
-    </ul>
-  </nav>
+  <React.StrictMode>
+    <nav>
+      <ul style={{ display: "flex", listStyle: "none", margin: 0, padding: 0 }}>
+        <li style={{ padding: "8px" }}>
+          <a href="/" onClick={navigateToUrl}>
+            Home
+          </a>
+        </li>
+        <li style={{ padding: "8px" }}>
+          <a href="/react" onClick={navigateToUrl}>
+            React
+          </a>
+        </li>
+      </ul>
+    </nav>
+  </React.StrictMode>
 );
 
 const lifecycles = singleSpaReact({