patch 8.2.0381: using freed memory with :lvimgrep and autocommand

Problem:    Using freed memory with :lvimgrep and autocommand. (extracted from
            POC by Dominique Pelle)
Solution:   Avoid deleting a dummy buffer used in a window. (closes #5777)

src/version.c

@@ -738,6 +738,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    381,
 /**/
     380,
 /**/