deps: update vstest monorepo to v17.6.0

[renovate[bot]]

This PR contains the following updates:

Package	Type	Update	Change
Microsoft.NET.Test.Sdk	nuget	minor	17.5.0 -> 17.6.0
Microsoft.TestPlatform.ObjectModel	nuget	minor	17.5.0 -> 17.6.0

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Release Notes

microsoft/vstest

### [`v17.6.0`](https://togithub.com/microsoft/vstest/releases/tag/v17.6.0) See the release notes [here](https://togithub.com/microsoft/vstest/blob/main/docs/releases.md#​1760).

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Configuration

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