[IoPoll] Take the wait() parameter validation test from php-src

php/php-src#23099 reports the negative timeout as argument #1 instead of #2,
which is what the polyfill already does, and covers both errors with a phpt.
It passes as is.

Author: nicolas-grekas

tests/Io/Poll/phpt/poll_ctx_wait.phpt

@@ -0,0 +1,24 @@
+--TEST--
+Io\Poll\Context::wait(): Parameter validation
+--FILE--
+<?php
+require_once __DIR__ . '/poll.inc';
+
+$poll_ctx = new Io\Poll\Context();
+
+try {
+    $poll_ctx->wait(timeout: Time\Duration::fromSeconds(1)->negate());
+} catch (Throwable $e) {
+    echo $e::class, ': ', $e->getMessage(), PHP_EOL;
+}
+
+try {
+    $poll_ctx->wait(maxEvents: -1);
+} catch (Throwable $e) {
+    echo $e::class, ': ', $e->getMessage(), PHP_EOL;
+}
+
+?>
+--EXPECT--
+ValueError: Io\Poll\Context::wait(): Argument #1 ($timeout) must not be negative
+ValueError: Io\Poll\Context::wait(): Argument #2 ($maxEvents) must be greater than 0