RunInFiberRequest - fix for when readonly property is downgraded

Author: ondrejmirtes

src/Analyser/Generator/RunInFiberRequest.php

@@ -15,13 +15,20 @@ final class RunInFiberRequest
 
 	public ?int $originLine = null;
 
+	/**
+	 * @readonly
+	 * @var callable(): T
+	 */
+	public mixed $callback;
+
 	/**
 	 * @param callable(): T $callback
 	 */
 	public function __construct(
-		public readonly mixed $callback,
+		mixed $callback,
 	)
 	{
+		$this->callback = $callback;
 		$trace = debug_backtrace(DEBUG_BACKTRACE_IGNORE_ARGS, 1);
 		$this->originFile = $trace[0]['file'] ?? null;
 		$this->originLine = $trace[0]['line'] ?? null;