patch 8.2.1650: Vim9: result of && and || expression is not bool in script

Problem:    Vim9: result of && and || expression cannot be assigned to a bool
            at the script level.
Solution:   Add the VAR_BOOL_OK flag.  Convert to bool when needed.
diff --git a/src/testdir/test_vim9_script.vim b/src/testdir/test_vim9_script.vim
index c454ffe..bd0a5c8 100644
--- a/src/testdir/test_vim9_script.vim
+++ b/src/testdir/test_vim9_script.vim
@@ -66,13 +66,13 @@
     let flag: bool = GetFlag()
     assert_equal(true, flag)
     flag = 0
-    # assert_equal(false, flag)
+    assert_equal(false, flag)
     flag = 1
-    # assert_equal(true, flag)
-    # flag = 99 || 123
-    # assert_equal(true, flag)
-    # flag = 'yes' && []
-    # assert_equal(false, flag)
+    assert_equal(true, flag)
+    flag = 99 || 123
+    assert_equal(true, flag)
+    flag = 'yes' && []
+    assert_equal(false, flag)
   END
   CheckScriptSuccess(lines)
   CheckDefAndScriptFailure(['let x: bool = 2'], 'E1012:')