Update WorkerOptions to have a `URI` property instead of `host` name and `port` number

This is related to https://github.com/Azure/azure-functions-powershell-worker/issues/992.

We are updating the logic to parse command-line arguments that the PowerShell language worker receives from the Functions Host. Currently, we are adding support to parse the new arguments, which are prefixed with functions-.

After the Functions Host changes have propagated, and we have a Core Tools version with this new Functions Host, we should remove parsing support for the old arguments. When doing this work, we should also consider adding a Uri property to the `WorkerOptions` type and assigning `workerArgs.FunctionsUri` to it. With this update, we can avoid rebuilding the [uri string](https://github.com/Azure/azure-functions-powershell-worker/blob/ea281afa59783045f2fc375055b9f6b50e79fec0/src/Messaging/MessagingStream.cs#L23-L25) inside the `MessagingStream` method and pass the `WorkerOptions` instance to that method instead.