fix: abort and reschedule $effect.pre when necessary (#16335)

* unskip failing test

* fix

* tidy up

* skip_no_async

* add comment

Author: Rich-Harris

packages/svelte/tests/runtime-runes/samples/effect-order-7/_config.js

@@ -2,14 +2,18 @@ import { flushSync } from 'svelte';
 import { test } from '../../test';
 
 export default test({
-	skip: true,
+	// For this to work in non-async mode, we would need to abort
+	// inside `#traverse_effect_tree`, which would be very
+	// complicated and annoying. Since this hasn't been
+	// a real issue (AFAICT), we ignore it
+	skip_no_async: true,
 
-	async test({ assert, target, logs }) {
+	async test({ target }) {
 		const [open, close] = target.querySelectorAll('button');
 
 		flushSync(() => open.click());
-		flushSync(() => close.click());
 
-		assert.deepEqual(logs, [true]);
+		// if the effect queue isn't aborted after the state change, this will throw
+		flushSync(() => close.click());
 	}
 });