Update .NET Version to 9.0

[Copilot]

Updates the project to target .NET 9.0, including CI/CD pipeline configuration.

Changes

• Project files: Updated TargetFramework from net8.0 to net9.0
  • AspNetCore.Utilities.CloudStorage.csproj
  • AspNetCore.Utilities.CloudStorage.Tests.csproj
• GitHub Actions workflows: Updated dotnet-version from 8.0.x to 9.0.x
  • ci-build.yml
  • release-build.yml

Original prompt

---

This section details on the original issue you should resolve

<issue_title>Update .NET Version</issue_title>
<issue_description>Update .NET to 9.0 including build</issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes Update .NET Version #79

---

💡 You can make Copilot smarter by setting up custom instructions, customizing its development environment and configuring Model Context Protocol (MCP) servers. Learn more Copilot coding agent tips in the docs.

[coderabbitai]

Important

Review skipped

Bot user detected.

To trigger a single review, invoke the @coderabbitai review command.

You can disable this status message by setting the reviews.review_status to false in the CodeRabbit configuration file.

---

_{Comment @coderabbitai help to get the list of available commands and usage tips.}