patch 8.2.0127: some buffer commands work in a popup window

Problem:    Some buffer commands work in a popup window.
Solution:   Disallow :bnext, :bprev, etc. (Naruhiko Nishino, closes #5494)
diff --git a/src/version.c b/src/version.c
index 71aecc8..d6fa59c 100644
--- a/src/version.c
+++ b/src/version.c
@@ -743,6 +743,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    127,
+/**/
     126,
 /**/
     125,