Incorrect attribute definition `access_groups` in `CardholderDetail` as `[list]`

**Describe the bug**
```python
class CardholderDetail(
AppBaseModel,
IdentityMixin,
HrefMixin,
):
"""Displays a table of cardholders

Gallagher command centre offers a summary of all the cardholders
provisioned on the system. This command presents a summary table
with the aim of using the identifier to get detailed information.

"""

# snip
personal_data_definitions: list[CardholderPersonalDataDefinition] = []
cards: list[CardholderCardSummary] = []
access_groups: Optional[list] = None
```

`access_groups: Optional[list] = None` parses `access_groups` assigned to the Cardholder as a `dict` it should ideally parse as a

**To Reproduce**
1. Fetch a cardholder
2. Attempt to access `cardholder.access_groups`
3. You get a `dict`

**Expected behavior**
1. I expect to access a `AccessGroupSummary`

**Screenshots**
NA

**Desktop (please complete the following information):**
NA

**Smartphone (please complete the following information):**
NA

**Additional context**
NA