patch 8.2.4218: illegal memory access with bracketed paste in Ex mode

Problem:    Illegal memory access with bracketed paste in Ex mode.
Solution:   Reserve space for the trailing NUL.

src/edit.c

@@ -4452,7 +4452,8 @@ bracketed_paste(paste_mode_T mode, int drop, garray_T *gap)
 		    break;
 
 		case PASTE_EX:
-		    if (gap != NULL && ga_grow(gap, idx) == OK)
+		    // add one for the NUL that is going to be appended
+		    if (gap != NULL && ga_grow(gap, idx + 1) == OK)
 		    {
 			mch_memmove((char *)gap->ga_data + gap->ga_len,
 							     buf, (size_t)idx);

src/testdir/test_paste.vim

@@ -90,6 +90,9 @@ func Test_paste_ex_mode()
   unlet! foo
   call feedkeys("Qlet foo=\"\<Esc>[200~foo\<CR>bar\<Esc>[201~\"\<CR>vi\<CR>", 'xt')
   call assert_equal("foo\rbar", foo)
+
+  " pasting more than 40 bytes
+  exe "norm Q\<PasteStart>0000000000000000000000000000000000000000000000000000000000000000000000\<C-C>"
 endfunc
 
 func Test_paste_onechar()

src/version.c

@@ -750,6 +750,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    4218,
 /**/
     4217,
 /**/