[Security] Update .NET SDK to latest patch version

This change updates to the latest patch version for the .NET SDK which contains the latest security fixes.

Release notes:
* [8.0.4](https://github.com/dotnet/core/blob/main/release-notes/8.0/8.0.4/8.0.4.md)
* [8.0.5](https://github.com/dotnet/core/blob/main/release-notes/8.0/8.0.5/8.0.5.md)
* [8.0.6](https://github.com/dotnet/core/blob/main/release-notes/8.0/8.0.6/8.0.6.md)

The following CVEs will be addressed by this update:
* [CVE-2024-21409](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2024-21409)
* [CVE-2024-30045](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2024-30045)
* [CVE-2024-30046](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2024-30046)
* [CVE-2024-20672](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2024-20672)

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For feedback or questions about this PR, please contact the [Gardener team](mailto:gardener@microsoft.com).

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This change was automatically generated by [1ES Gardener](https://eng.ms/docs/cloud-ai-platform/devdiv/one-engineering-system-1es/1es-docs/gardener/1es-gardener) (a [MerlinBot](https://aka.ms/MerlinBot) extension) which is an initiative by the 1ES team to help repos stay up-to-date with latest tools, features, and best practices.

Author: MerlinBot

global.json

@@ -1,5 +1,5 @@
 {
     "sdk": {
-        "version": "8.0.202"
+        "version": "8.0.206"
     }
 }