Ignore ExitStatus exceptions

This should fix these errors:

    [wasm test] [23:10:04] dbug: Reached wasm exit
    [wasm test] [23:10:04] info: node:internal/process/promises:246
    [wasm test] [23:10:04] info:           triggerUncaughtException(err, true /* fromPromise */);
    [wasm test] [23:10:04] info:           ^
    [wasm test] [23:10:04] info:
    [wasm test] [23:10:04] info: [UnhandledPromiseRejection: This error originated either by throwing inside of an async function without a catch block, or by rejecting a promise which was not handled with .catch(). The promise rejected with the reason "#<ExitStatus>".] {
    [wasm test] [23:10:04] info:   code: 'ERR_UNHANDLED_REJECTION'
    [wasm test] [23:10:04] info: }
    [wasm test] [23:10:04] info:
    [wasm test] [23:10:04] info: Node.js v17.3.1
    [wasm test] [23:10:04] info: Process node.exe exited with 1

src/mono/wasm/test-main.js

@@ -23,6 +23,16 @@ if (is_node && process.versions.node.split(".")[0] < 14) {
     throw new Error(`NodeJS at '${process.execPath}' has too low version '${process.versions.node}'`);
 }
 
+if (is_node) {
+    // the emscripten 3.1.34 stopped handling these when MODULARIZE is enabled
+    process.on('uncaughtException', function(ex) {
+        // ignore ExitStatus exceptions
+        if (ex !== 'unwind' && !(ex instanceof ExitStatus) && !(ex.context instanceof ExitStatus)) {
+          throw ex;
+        }
+      });
+}
+
 if (!is_node && !is_browser && typeof globalThis.crypto === 'undefined') {
     // **NOTE** this is a simple insecure polyfill for testing purposes only
     // /dev/random doesn't work on js shells, so define our own