Nuget upgrade.

Author: Jaben

lib/Gotenberg.Sharp.Api.Client.csproj

@@ -23,7 +23,7 @@
     </Description>
     <IncludeSymbols>True</IncludeSymbols>
     <PackageReleaseNotes>
-      Upgraded to support Gotenberg v7.
+      Upgraded to support Gotenberg v7 -- this version no longer works with Gotenberg v6.
     </PackageReleaseNotes>    
     <PackageLicenseUrl>http://www.apache.org/licenses/LICENSE-2.0</PackageLicenseUrl>
     <PackageProjectUrl>https://github.com/ChangemakerStudios/GotenbergSharpApiClient</PackageProjectUrl>
@@ -38,7 +38,7 @@
   </ItemGroup>
 
   <ItemGroup>
-    <PackageReference Include="JetBrains.Annotations" Version="2021.3.0" />
+    <PackageReference Include="JetBrains.Annotations" Version="2022.1.0" />
     <PackageReference Include="MimeMapping" Version="1.0.1.37" />
     <PackageReference Include="Newtonsoft.Json" Version="13.0.1" />
   </ItemGroup>