[phpstorm-stubs] fix 'since' annotation for pcntl_waitid function signature

Author: isfedorov

pcntl/pcntl.php

@@ -495,7 +495,9 @@ function pcntl_signal_get_handler(int $signal) {}
  */
 function pcntl_unshare(int $flags): bool {}
 
-#[PhpStormStubsElementAvailable(from: '8.4')]
+/**
+ * @since 8.4
+ */
 function pcntl_waitid(int $idtype = P_ALL, ?int $id = null, &$info = [], int $flags = WEXITED, #[PhpStormStubsElementAvailable(from: '8.5')] &$resource_usage = []): bool {}
 /**
  * @since 8.4