Update Orleans App Service sample to work on App Service Linux

[ReubenBond]

Purpose

This PR updates the sample to .NET 8.0, Orleans v8.2.0, and updates other packages. It changes configuration so that the sample can be deployed to App Service Linux.

In deploying to App Service Linux, there are some requirements:

• Enable VNet integration
• Set VNetPrivatePortsCount to 2 or greater:

az webapp config set -g <resource-group-name> --subscription <subscription-id> -n <app-service-app-name> --generic-configurations '{\"vnetPrivatePortsCount\": "4"}'

Does this introduce a breaking change?

[ ] Yes
[x] No

Pull Request Type

What kind of change does this Pull Request introduce?

[x] Bugfix
[ ] Feature
[x] Code style update (formatting, local variables)
[ ] Refactoring (no functional changes, no api changes)
[ ] Documentation content changes
[x] Other... Please describe: update to new packages, implement App Service Linux support