## Description

Make sure all fields are correctly serialized in camelcase. This was not
the case for `typeParameters` or for `queryPayload`.

## Test Plan

E2E tests

```
sui-graphql-e2e-tests$ cargo nextest run -j 1 --features pg_integration
```

Also, do an audit of all GraphQL responses in E2E tests to make sure
they are appropriately formatted:

```
sui-graphql-e2e-tests/tests$ sed -n '/^Response: {$/,/^}$/p' **/*.exp \
  | sed 's/Response: //'                                              \
  | jq -r 'paths | map(tostring) | join(".")'                         \
  | awk -F'.' '$NF ~ /[a-zA-Z]+_/ && $0 !~ /\.json\./ { print $NF }'
```

(all remaining names that include underscores come from field aliases).