patch 8.2.0428: buffer name may leak

Problem:    Buffer name may leak.
Solution:   Free the buffer name before overwriting it.
diff --git a/src/version.c b/src/version.c
index b954243..e27b773 100644
--- a/src/version.c
+++ b/src/version.c
@@ -739,6 +739,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    428,
+/**/
     427,
 /**/
     426,