## Bug description

strtobool is used in several places where it will cause deprecation warning in Pythin 3.10 and error in Python 3.12 since distutils will be removed in Python 3.12 .

Reference : https://www.python.org/dev/peps/pep-0632/

```
rg distutils                     
posthog/api/annotation.py
1:from distutils.util import strtobool

posthog/api/dashboard.py
2:from distutils.util import strtobool

posthog/api/insight.py
1:from distutils.util import strtobool

posthog/models/filters/mixins/common.py
4:from distutils.util import strtobool

posthog/settings.py
17:from distutils.util import strtobool
```

## Expected behavior

It's a good idea to vendor in the function as it's a short one.

## Environment

- [ ] PostHog Cloud
- [ ] self-hosted PostHog, version/commit: _please provide_


#### *Thank you* for your bug report – we love squashing them!

posthog/models/filters/mixins/common.py
@cached_property
    def selector(self) -> Optional[str]:
        return self._data.get(SELECTOR, None)
    @include_dict
    def selector_to_dict(self):
        return {"selector": self.selector} if self.selector else {}
class ShownAsMixin(BaseParamMixin):
    @cached_property
    def shown_as(self) -> Optional[str]:
        return self._data.get(SHOWN_AS, None)
    @include_dict
    def shown_as_to_dict(self):
        return {"shown_as": self.shown_as} if self.shown_as else {}
class FilterTestAccountsMixin(BaseParamMixin):
    @cached_property
    def filter_test_accounts(self) -> Optional[bool]:
        setting = self._data.get(FILTER_TEST_ACCOUNTS, None)
        if setting == True or setting == "true":
            return True
        return None
    @include_dict
    def filter_out_team_members_to_dict(self):
        return {"filter_test_accounts": self.filter_test_accounts} if self.filter_test_accounts else {}
class FormulaMixin(BaseParamMixin):