Revert "Attempt to deflake loaf-script-block by disabling one of its tests"

This reverts commit 7c0ab2fd09400b6f3bc32f92786d616f057bb27e.

Reason for revert: test is still flaky

Original change's description:
> Attempt to deflake loaf-script-block by disabling one of its tests
>
> Bug: 1422630
> Change-Id: I2935f31c8ada734ae7fb62a06e1475033f1d77c6
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4356273
> Reviewed-by: Yoav Weiss <yoavweiss@chromium.org>
> Auto-Submit: Noam Rosenthal <nrosenthal@chromium.org>
> Commit-Queue: Yoav Weiss <yoavweiss@chromium.org>
> Cr-Commit-Position: refs/heads/main@{#1119840}

Bug: 1422630
Change-Id: I09e6f02e34de7ba2dfaeee2a64fcd1c70aff5b83
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4355144
Reviewed-by: Florian Leimgruber <fleimgruber@google.com>
Bot-Commit: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Commit-Queue: Noam Rosenthal <nrosenthal@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1119944}
diff --git a/long-animation-frame/tentative/loaf-script-block.html b/long-animation-frame/tentative/loaf-script-block.html
index c832f79..f896a73 100644
--- a/long-animation-frame/tentative/loaf-script-block.html
+++ b/long-animation-frame/tentative/loaf-script-block.html
@@ -36,6 +36,12 @@
     document.body.appendChild(script);
 }, new URL("resources/busy.js", location.href).href, "module-script");
 
-// TODO: add test for dynamic import()
+test_self_script_block(t => {
+    const script = document.createElement("script");
+    script.type = "module";
+    script.innerHTML = `import("./resources/busy.js?import");`;
+    document.body.appendChild(script);
+}, new URL("resources/busy.js?import", location.href).href, "execute-script");
+
 </script>
 </body>