Fix canister id in test app (#1857)

The test app canister id replacement mechanism broke
(presumably quite a while ago). This fixes PR fixes it.

demos/test-app/lib.rs

@@ -216,10 +216,10 @@ lazy_static! {
         let canister_id = api::id();
         let index_html = include_str!("dist/index.html");
 
-        // the string we are replacing here is inserted by webpack during the front-end build
+        // the string we are replacing here is inserted by vite during the front-end build
         let index_html = index_html.replace(
-            r#"<script defer src="bundle.js"></script>"#,
-            &format!(r#"<script>var canisterId = '{canister_id}';</script><script defer="defer" src="bundle.js"></script>"#).to_string()
+            r#"<script type="module" crossorigin src="/index.js"></script>"#,
+            &format!(r#"<script>var canisterId = '{canister_id}';</script><script type="module" crossorigin src="/index.js"></script>"#).to_string()
         );
         index_html
     };

demos/test-app/src/index.html

@@ -62,7 +62,7 @@ <h1>Contact the IC</h1>
       <label for="canisterId" style="display: inline-block; width: 120px"
         >Canister ID:
       </label>
-      <input type="text" id="canisterId" value="kvusz-kaaaa-aaaad-aabwa-cai" />
+      <input type="text" id="canisterId" />
     </div>
     <div>
       <button id="whoamiBtn">Who Am I?</button>