Revert "[wasm] Temporarily disable --wasm-shared-engine test."

This reverts commit 53fe5c44.

Reason for revert: Test can be re-enabled, a fix for the flake landed by now.

Original change's description:
> [wasm] Temporarily disable --wasm-shared-engine test.
> 
> R=​leszeks@chromium.org
> 
> Change-Id: Ib037c43571cda0e2da3c6da3d763cfe27c797413
> Reviewed-on: https://chromium-review.googlesource.com/1150033
> Reviewed-by: Leszek Swirski <leszeks@chromium.org>
> Commit-Queue: Michael Starzinger <mstarzinger@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#54692}

TBR=mstarzinger@chromium.org,leszeks@chromium.org

# Not skipping CQ checks because original CL landed > 1 day ago.

Change-Id: I406740898d896a18eef365cdd20581d5de84023a
Reviewed-on: https://chromium-review.googlesource.com/1151407Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Commit-Queue: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#54731}

test/mjsunit/wasm/worker-module.js

@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// Flags: --no-wasm-disable-structured-cloning
+// Flags: --wasm-shared-engine --no-wasm-disable-structured-cloning
 
 load("test/mjsunit/wasm/wasm-constants.js");
 load("test/mjsunit/wasm/wasm-module-builder.js");