Bump TUnit from 1.2.11 to 1.3.15 (#399)

---
updated-dependencies:
- dependency-name: TUnit
  dependency-version: 1.3.15
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

Directory.Packages.props

@@ -21,7 +21,7 @@
     <PackageVersion Include="NUnit" Version="4.4.0" />
     <PackageVersion Include="NUnit3TestAdapter" Version="5.2.0" />
     <PackageVersion Include="System.Formats.Asn1" Version="9.0.10" />
-    <PackageVersion Include="TUnit" Version="1.2.11" />
+    <PackageVersion Include="TUnit" Version="1.3.15" />
     <PackageVersion Include="xunit.runner.visualstudio" Version="3.1.5" />
     <PackageVersion Include="xunit.v3" Version="3.2.0" />
   </ItemGroup>