Bump Microsoft.OpenApi from 1.6.22 to 3.7.0

---
updated-dependencies:
- dependency-name: Microsoft.OpenApi
  dependency-version: 3.7.0
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

Author: dependabot[bot]

backend/src/Accanto.Api/Accanto.Api.csproj

@@ -13,7 +13,7 @@
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
       <PrivateAssets>all</PrivateAssets>
     </PackageReference>
-    <PackageReference Include="Microsoft.OpenApi" Version="1.6.22" />
+    <PackageReference Include="Microsoft.OpenApi" Version="3.7.0" />
     <PackageReference Include="Serilog.AspNetCore" Version="9.0.0" />
     <PackageReference Include="Serilog.Sinks.Seq" Version="9.0.0" />
     <PackageReference Include="Swashbuckle.AspNetCore" Version="7.2.0" />