## Bug description

I have lost edit permissions to a [dashboard I created](https://app.posthog.com/dashboard/28987), despite still being listed as the owner of the dashboard

## Expected behavior

I should still be able to edit the dashboard

## How to reproduce

I noticed this problem after adding a new insight, but this doesn't appear to be the cause of the issue. I've duplicated the dashboard to restore access and adding a new insight didn't appear to cause the issue 

## Environment

- [x] PostHog Cloud
- [ ] self-hosted PostHog (ClickHouse-based), version/commit: _please provide_
- [ ] self-hosted PostHog (Postgres-based, legacy), version/commit: _please provide_

## Additional context

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

posthog/api/dashboard.py
message = "You don't have edit permissions for this dashboard."
    def has_object_permission(self, request: Request, view, dashboard) -> bool:
        if request.method in SAFE_METHODS:
            return True
        return dashboard.can_user_edit(cast(User, request.user).id)
class DashboardSerializer(TaggedItemSerializerMixin, serializers.ModelSerializer):
    items = serializers.SerializerMethodField()
    created_by = UserBasicSerializer(read_only=True)
    use_template = serializers.CharField(write_only=True, allow_blank=True, required=False)
    use_dashboard = serializers.IntegerField(write_only=True, allow_null=True, required=False)
    effective_privilege_level = serializers.SerializerMethodField()
    class Meta: