Updated nuget packages.

src/Discord.Net.Core/Discord.Net.Core.csproj

@@ -8,10 +8,10 @@
     <TargetFrameworks Condition=" '$(OS)' != 'Windows_NT' ">netstandard2.0;netstandard2.1</TargetFrameworks>
   </PropertyGroup>
   <ItemGroup>
-    <PackageReference Include="Newtonsoft.Json" Version="12.0.2" />
-    <PackageReference Include="System.Collections.Immutable" Version="1.3.1" />
-    <PackageReference Include="System.Interactive.Async" Version="4.0.0" />
-    <PackageReference Include="IDisposableAnalyzers" Version="2.1.2">
+    <PackageReference Include="Newtonsoft.Json" Version="12.0.3" />
+    <PackageReference Include="System.Collections.Immutable" Version="1.7.1" />
+    <PackageReference Include="System.Interactive.Async" Version="4.1.1" />
+    <PackageReference Include="IDisposableAnalyzers" Version="3.4.1">
       <PrivateAssets>all</PrivateAssets>
     </PackageReference>
   </ItemGroup>