patch 8.2.3428: using freed memory when replacing

Problem:    Using freed memory when replacing. (Dhiraj Mishra)
Solution:   Get the line pointer after calling ins_copychar().

src/testdir/test_edit.vim

@@ -1895,4 +1895,16 @@ func Test_edit_revins()
   bw!
 endfunc
 
+" Test for getting the character of the line below after "p"
+func Test_edit_put_CTRL_E()
+  set encoding=latin1
+  new
+  let @" = ''
+  sil! norm orggRx
+  sil! norm pr
+  call assert_equal(['r', 'r'], getline(1, 2))
+  bwipe!
+  set encoding=utf-8
+endfunc
+
 " vim: shiftwidth=2 sts=2 expandtab