Fix dash symbol highlight in enums

dash is allowed value in an enum

```
ProcessDefinitionKey (
  cs-kek |
  cs-lel-local |
)
```
 
![image](https://user-images.githubusercontent.com/30667180/120781741-664c8d00-c53a-11eb-9175-9e3563286ed5.png)


DOD:

It also needs a highlighting
