patch 8.2.1086: possibly using freed memory when text properties used

Problem:    Possibly using freed memory when text properties used when
            changing indent of a line.
Solution:   Compute the offset before calling ml_replace().
diff --git a/src/version.c b/src/version.c
index 65dffff..6f6e481 100644
--- a/src/version.c
+++ b/src/version.c
@@ -755,6 +755,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1086,
+/**/
     1085,
 /**/
     1084,