patch 8.2.2793: MS-Windows: string literals are writable with MSVC

Problem:    MS-Windows: string literals are writable with MSVC.
Solution:   Add the /GF compiler flag.  Make mch_write() safer. (Ken Takata,
            closes #8133)

src/version.c

@@ -750,6 +750,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    2793,
 /**/
     2792,
 /**/