patch 8.2.0084: complete item "user_data" can only be a string

Problem:    Complete item "user_data" can only be a string.
Solution:   Accept any type of variable. (closes #5412)
diff --git a/src/eval.c b/src/eval.c
index 04abbab..2a2d9d4 100644
--- a/src/eval.c
+++ b/src/eval.c
@@ -2656,7 +2656,7 @@
     case '#':	if ((*arg)[1] == '{')
 		{
 		    ++*arg;
-		    ret = dict_get_tv(arg, rettv, evaluate, TRUE);
+		    ret = eval_dict(arg, rettv, evaluate, TRUE);
 		}
 		else
 		    ret = NOTDONE;
@@ -2668,7 +2668,7 @@
      */
     case '{':	ret = get_lambda_tv(arg, rettv, evaluate);
 		if (ret == NOTDONE)
-		    ret = dict_get_tv(arg, rettv, evaluate, FALSE);
+		    ret = eval_dict(arg, rettv, evaluate, FALSE);
 		break;
 
     /*