convert_camel_case_to_snake produces bad results in two cases

[ofer-pd]

Currently converts as follows:

FOO_bar  ->  fo_o_bar    # would prefer foo_bar
FOO_BAR  ->  fo_o_bar    # would prefer foo_bar

Could be fixed by adding a line after: https://github.com/mirumee/ariadne/blob/main/ariadne/utils.py#L70

```python
            or (
                i < max_index
                and graphql_name[i] != c
                and graphql_name[i + 1] == lowered_name[i + 1]
                and graphql_name[ i + 1 ] != "_"        # <--- NEW LINE
            )

Thoughts?

---

UPDATE: I just came across another bad conversion case at work:

S3_BUCKET  ->  s_3__bucket    # would prefer s3_bucket

If there's interest in this, I can work on a patch. Otherwise, I'll just fix it for myself with a custom converter.

[rafalp]

Please contribute a patch, I would love to include a fix in new release I am planning sometime before xmas.

[ofer-pd]

I don't think I'll be able to get anything done before xmas - got a ton of work that needs to be finished by end of year.

I'll jump on this as soon as I can get some breathing room at work.