Add net8 enabled flag for in-proc Csx samples

[MaddyDev]

Description

This pull request updates the C# Script (Csx) samples to run on the .NET 8 in-process hosting model.

Changes:

Added the FUNCTIONS_INPROC_NET8_ENABLED flag and set it to "1" in the local.settings.json file for the C# Script samples.
Reasoning:

The .NET 8 in-process model for Azure Functions requires this application setting to be explicitly enabled for C# Script projects. Without this flag, the function host would default to an older execution model.

This change ensures that the samples are up-to-date with the latest Azure Functions runtime capabilities and can be executed and tested correctly on the .NET 8 framework. This aligns the sample's configuration with the recommended setup for running C# Script functions on .NET 8.

Code Changes

• Unit tests are added, if possible
• Integration tests are added if the change is modifying existing behavior of one or more of the bindings
• New or changed code follows the C# style guidelines defined in .editorconfig
• All changes MUST be backwards compatible and changes to the shared az_func.GlobalState table must be compatible with all prior versions of the extension
• Use the ILogger instance to log relevant information, especially information useful for debugging or troubleshooting
• Use async and await for all long-running operations
• Ensure proper usage and propagation of CancellationToken
• T-SQL is safe from SQL Injection attacks through the use of SqlParameters and proper escaping/sanitization of input

Dependencies

• If updating dependencies, run dotnet restore --force-evaluate to update the lock files and ensure that there are NO major versions updates in either src/packages.lock.json or Worker.Extensions.Sql/src/packages.lock.json. If there are, contact the dev team for instructions.

Documentation

• Add samples if the change is modifying or adding functionality
• Update relevant documentation in the docs