No error when typedef is missing semicolon

This is permitted in Haxe:
```haxe
typedef A = String
```
I think it is a bug to do with allowing:
```haxe
typedef A = { a: String }
```

The code seems to be found here: https://github.com/HaxeFoundation/haxe/blob/development/src/syntax/grammar.mly#L284-L286

We should instead do something like we do here:
https://github.com/HaxeFoundation/haxe/blob/development/src/syntax/grammar.mly#L100

This is inconsistent with the rest of the language, and causes issues with the vshaxe parser:
https://github.com/vshaxe/vshaxe/issues/24
https://github.com/vshaxe/haxe-TmLanguage/issues/54