Bump DiffPlex from 1.7.2 to 1.9.0 (#2220)

---
updated-dependencies:
- dependency-name: DiffPlex
  dependency-version: 1.9.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

Author: dependabot[bot]

Directory.Packages.props

@@ -88,7 +88,7 @@
   <ItemGroup>
     <PackageVersion Include="Aspire.Hosting.AppHost" Version="13.0.0" />
     <PackageVersion Include="AngleSharp.Diffing" Version="1.1.0" />
-    <PackageVersion Include="DiffPlex" Version="1.7.2" />
+    <PackageVersion Include="DiffPlex" Version="1.9.0" />
     <PackageVersion Include="FluentAssertions" Version="7.2.0" />
     <PackageVersion Include="FsUnit.xUnit" Version="7.0.1" />
     <PackageVersion Include="GitHubActionsTestLogger" Version="2.4.1" />