fix: bump DocumentFormat.OpenXml in the dependencies group

Bumps the dependencies group with 1 update: [DocumentFormat.OpenXml](https://github.com/dotnet/Open-XML-SDK).


Updates `DocumentFormat.OpenXml` from 3.1.0 to 3.1.1
- [Release notes](https://github.com/dotnet/Open-XML-SDK/releases)
- [Changelog](https://github.com/dotnet/Open-XML-SDK/blob/main/CHANGELOG.md)
- [Commits](dotnet/Open-XML-SDK@v3.1.0...v3.1.1)

---
updated-dependencies:
- dependency-name: DocumentFormat.OpenXml
  dependency-type: direct:production
  update-type: version-update:semver-patch
  dependency-group: dependencies
...

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

src/FileCurator/FileCurator.csproj

@@ -47,7 +47,7 @@
 
   <ItemGroup>
     <PackageReference Include="BigBook" Version="5.1.56" />
-    <PackageReference Include="DocumentFormat.OpenXml" Version="3.1.0" />
+    <PackageReference Include="DocumentFormat.OpenXml" Version="3.1.1" />
     <PackageReference Include="HtmlAgilityPack" Version="1.11.67" />
     <PackageReference Include="MimeKit" Version="4.8.0" />
     <PackageReference Include="PdfPig" Version="0.1.9" />