patch 8.2.1647: Vim9: result of expression with && and || is not a bool

Problem:    Vim9: result of expression with && and || cannot be assigned to a
            bool variable.
Solution:   Add the TTFLAG_BOOL_OK flag and convert the value if needed.

src/version.c

@@ -750,6 +750,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1647,
 /**/
     1646,
 /**/