Fix bad example in standardization meeting notes
The example about the lack of an `open_contract` primitive operation is not relevant. Probably a blind copy-paste.
@@ -224,7 +224,7 @@ open_contract(#(open_contract(T))) = open_contract(T)
else contract label value in
//cannot do
- foo | #Nullable (C1 & C2 & C3)
+ foo | #Nullable (Num -> Num)
```
- `#` is verbose: should we remove it? But in current situation, it is nice to
embed value syntax in the type syntax as in
