Bump Verify.DiffPlex from 3.1.1 to 3.1.2 in /src

Bumps [Verify.DiffPlex](https://github.com/VerifyTests/Verify.DiffPlex) from 3.1.1 to 3.1.2.
- [Release notes](https://github.com/VerifyTests/Verify.DiffPlex/releases)
- [Commits](VerifyTests/Verify.DiffPlex@3.1.1...3.1.2)

---
updated-dependencies:
- dependency-name: Verify.DiffPlex
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>

src/Directory.Packages.props

@@ -9,7 +9,7 @@
     <PackageVersion Include="ProjectDefaults" Version="1.0.139" />
     <PackageVersion Include="Paramore.Brighter" Version="9.9.6" />
     <PackageVersion Include="Verify" Version="27.0.1" />
-    <PackageVersion Include="Verify.DiffPlex" Version="3.1.1" />
+    <PackageVersion Include="Verify.DiffPlex" Version="3.1.2" />
     <PackageVersion Include="Verify.XunitV3" Version="27.0.1" />
     <PackageVersion Include="xunit.v3" Version="0.4.0-pre.20" />
     <PackageVersion Include="xunit.runner.visualstudio" Version="3.0.0-pre.35" />