Added Discord.Net.Webhook to pack list

pack.ps1

@@ -8,6 +8,8 @@ dotnet pack "src\Discord.Net.Rpc\Discord.Net.Rpc.csproj" -c "Release" -o "../../
 if ($LastExitCode -ne 0) { $host.SetShouldExit($LastExitCode) }
 dotnet pack "src\Discord.Net.Commands\Discord.Net.Commands.csproj" -c "Release" -o "../../artifacts" --no-build /p:BuildNumber="$Env:BUILD" /p:IsTagBuild="$Env:APPVEYOR_REPO_TAG"
 if ($LastExitCode -ne 0) { $host.SetShouldExit($LastExitCode) }
+dotnet pack "src\Discord.Net.Webhook\Discord.Net.Webhook.csproj" -c "Release" -o "../../artifacts" --no-build /p:BuildNumber="$Env:BUILD" /p:IsTagBuild="$Env:APPVEYOR_REPO_TAG"
+if ($LastExitCode -ne 0) { $host.SetShouldExit($LastExitCode) }
 dotnet pack "src\Discord.Net.Providers.WS4Net\Discord.Net.Providers.WS4Net.csproj" -c "Release" -o "../../artifacts" --no-build /p:BuildNumber="$Env:BUILD" /p:IsTagBuild="$Env:APPVEYOR_REPO_TAG"
 if ($LastExitCode -ne 0) { $host.SetShouldExit($LastExitCode) }
 dotnet pack "src\Discord.Net.Providers.UdpClient\Discord.Net.Providers.UdpClient.csproj" -c "Release" -o "../../artifacts" --no-build /p:BuildNumber="$Env:BUILD" /p:IsTagBuild="$Env:APPVEYOR_REPO_TAG"