Fix type coercion

src/Psalm/Internal/Analyzer/Statements/ReturnAnalyzer.php

@@ -590,6 +590,7 @@ class ReturnAnalyzer
      * If a function returns a closure, we try to infer the param/return types of
      * the inner closure.
      * @see \Psalm\Tests\ReturnTypeTest:756
+     * @param PhpParser\Node\Expr\Closure|PhpParser\Node\Expr\ArrowFunction $expr
      */
     private static function potentiallyInferTypesOnClosureFromParentReturnType(
         StatementsAnalyzer $statements_analyzer,