patch 8.2.1795: Vim9: operators && and || have a confusing result

Problem:    Vim9: operators && and || have a confusing result.
Solution:   Make the result a boolean.
diff --git a/src/testdir/test_vim9_cmd.vim b/src/testdir/test_vim9_cmd.vim
index 060b083..82d5f32 100644
--- a/src/testdir/test_vim9_cmd.vim
+++ b/src/testdir/test_vim9_cmd.vim
@@ -72,8 +72,8 @@
   var lines =<< trim END
       vim9script
       if 1 &&
-            2
-            || 3
+            true
+            || 1
         g:res = 42
       endif
       assert_equal(42, g:res)