feat: always use SWC Wasm fallback when running in WebContainer (#58081)

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### What?

Since the Wasm fallback was re-introduced in
https://github.com/vercel/next.js/pull/57906 I am now also adding a
check for detecting WebContainers so that it would always use the SWC
Wasm fallback. That's because WebContainers can't execute native
binaries.

I decided to not account for `NEXT_DISABLE_SWC_WASM` because it doesn't
make much sense and if someone had this enabled, it would always fail.
But if ya all think it's better to take this flag into account then I am
happy to change it.

packages/next/src/build/swc/index.ts

@@ -208,8 +208,10 @@ export async function loadBindings(
       (triple: any) =>
         !!triple?.raw && knownDefaultWasmFallbackTriples.includes(triple.raw)
     )
+    const isWebContainer = process.versions.webcontainer
     const shouldLoadWasmFallbackFirst =
-      !disableWasmFallback && unsupportedPlatform && useWasmBinary
+      (!disableWasmFallback && unsupportedPlatform && useWasmBinary) ||
+      isWebContainer
 
     if (!unsupportedPlatform && useWasmBinary) {
       Log.warn(