RecursionError: maximum recursion depth exceeded

Some repeated phrases causes model crash due to hitting max recursion depth. 
According to stacktrace issue originates from:

> ginza/bunsetu_recognizer.py  => **_children_except_clause_heads**  Line:347

Minimal example:

```python
    import spacy
    a = '漢字'*1000
    nlp = spacy.load('ja_ginza_electra')
    b = nlp(a)
```
