chore(deps): update dependency verify.tunit to 31.15.0 (#4287)

This PR contains the following updates:

| Package | Change |
[Age](https://docs.renovatebot.com/merge-confidence/) |
[Confidence](https://docs.renovatebot.com/merge-confidence/) |
|---|---|---|---|
| [Verify.TUnit](https://redirect.github.com/VerifyTests/Verify) |
`31.14.0` → `31.15.0` |
![age](https://developer.mend.io/api/mc/badges/age/nuget/Verify.TUnit/31.15.0?slim=true)
|
![confidence](https://developer.mend.io/api/mc/badges/confidence/nuget/Verify.TUnit/31.14.0/31.15.0?slim=true)
|

---

### Release Notes

<details>
<summary>VerifyTests/Verify (Verify.TUnit)</summary>

###
[`v31.15.0`](https://redirect.github.com/VerifyTests/Verify/compare/31.14.0...31.15.0)

[Compare
Source](https://redirect.github.com/VerifyTests/Verify/compare/31.14.0...31.15.0)

</details>

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src/Directory.Packages.props

@@ -54,7 +54,7 @@
     <PackageVersion Include="System.Text.Json" Version="10.0.5" />
     <PackageVersion Include="TUnit" Version="$(TUnitVersion)" />
     <PackageVersion Include="TUnit.Core" Version="$(TUnitVersion)" />
-    <PackageVersion Include="Verify.TUnit" Version="31.14.0" />
+    <PackageVersion Include="Verify.TUnit" Version="31.15.0" />
     <PackageVersion Include="Microsoft.Windows.CsWinRT" Version="2.3.0-prerelease.251115.2" />
     <PackageVersion Include="Microsoft.AspNetCore.Components" Version="$(AspNetVersion)" />
     <PackageVersion Include="Microsoft.Maui.Controls" Version="$(MauiVersion)" />