feat: implement anyOf component

## Describe the feature

Implement `anyOf` component:

```ts
let regex = buildRegex(
    anyOf("abcd"), // [abcd]
    oneOrMore(anyOf("abcd")), // [abcd]+
)
```

Ref: https://developer.apple.com/documentation/regexbuilder/characterclass/anyof(_:)-1s0kt

## Related Issues