patch 8.1.2108: cannot close the cmdline window from CmdWinEnter

Problem:    Cannot close the cmdline window from CmdWinEnter. (George Brown)
Solution:   Reset cmdwin_result earlier. (Christian Brabandt, closes #4980)
diff --git a/src/version.c b/src/version.c
index e2f0c92..469b759 100644
--- a/src/version.c
+++ b/src/version.c
@@ -754,6 +754,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    2108,
+/**/
     2107,
 /**/
     2106,