patch 8.1.1359: text property wrong after :substitute with backslash

Problem:    Text property wrong after :substitute with backslash.
Solution:   Adjust text property columns when removing backslashes.
            (closes #4397)

src/edit.c

@@ -4104,7 +4104,7 @@ replace_do_bs(int limit_col)
 
 	    --text_prop_frozen;
 	    adjust_prop_columns(curwin->w_cursor.lnum, curwin->w_cursor.col,
-					   (int)(len_now - len_before), FALSE);
+					   (int)(len_now - len_before), 0);
 	}
 #endif
     }