patch 8.2.1256: Vim9: type wrong after getting dict item in lambda

Problem:    Vim9: type wrong after getting dict item in lambda.
Solution:   Set the type to "any" after enforcing dict type. (closes #6491)

Author: brammool

src/testdir/test_vim9_expr.vim

@@ -1176,6 +1176,10 @@ def Test_expr7_lambda()
   let dl = [{'key': 0}, {'key': 22}]->filter({ _, v -> v['key'] })
   assert_equal([{'key': 22}], dl)
 
+  dl = [{'key': 12}, {'foo': 34}]
+  assert_equal([{'key': 12}], filter(dl,
+	{_, v -> has_key(v, 'key') ? v['key'] == 12 : 0}))
+
   call CheckDefFailure(["filter([1, 2], {k,v -> 1})"], 'E1069:')
 enddef
 

src/version.c

@@ -754,6 +754,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1256,
 /**/
     1255,
 /**/

src/vim9compile.c

@@ -3797,9 +3797,12 @@ compile_subscript(
 	    {
 		if ((*typep)->tt_type == VAR_DICT)
 		    *typep = (*typep)->tt_member;
-		else if (need_type(*typep, &t_dict_any, -2, cctx, FALSE)
-								       == FAIL)
-		    return FAIL;
+		else
+		{
+		    if (need_type(*typep, &t_dict_any, -2, cctx, FALSE) == FAIL)
+			return FAIL;
+		    *typep = &t_any;
+		}
 		if (may_generate_2STRING(-1, cctx) == FAIL)
 		    return FAIL;
 		if (generate_instr_drop(cctx, ISN_MEMBER, 1) == FAIL)