Upgrade neonpostgres library

As part of the work to address https://github.com/Azure/azure-sdk-for-net/issues/52974, neonpostgres was not upgraded due to generator issues. Here is the [commit](https://github.com/Azure/azure-sdk-for-net/pull/52975/commits/a7d3a87f527827b2e998a06077d09c783a749d7c) where the upgrade was reverted. This issue tracks the work to upgrade the library.