Fixed tag metapackage logic, fixed test error

pack.ps1

@@ -14,9 +14,9 @@ dotnet pack "src\Discord.Net.Providers.UdpClient\Discord.Net.Providers.UdpClient
 if ($LastExitCode -ne 0) { $host.SetShouldExit($LastExitCode) }
 
 if ($Env:APPVEYOR_REPO_TAG -eq "true") {
-    nuget pack src\Discord.Net\Discord.Net.nuspec -OutputDirectory "artifacts" -properties suffix="-$Env:BUILD"
+    nuget pack src\Discord.Net\Discord.Net.nuspec -OutputDirectory "artifacts" -properties suffix=""
 }
 else {
-    nuget pack src\Discord.Net\Discord.Net.nuspec -OutputDirectory "artifacts" -properties suffix=""
+    nuget pack src\Discord.Net\Discord.Net.nuspec -OutputDirectory "artifacts" -properties suffix="-$Env:BUILD"
 }
 if ($LastExitCode -ne 0) { $host.SetShouldExit($LastExitCode) }

test/Discord.Net.Tests/Discord.Net.Tests.csproj

@@ -1,5 +1,4 @@
 <Project Sdk="Microsoft.NET.Sdk" ToolsVersion="15.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
-  <Import Project="../../Discord.Net.targets" />
   <PropertyGroup>
     <OutputType>Exe</OutputType>
     <RootNamespace>Discord</RootNamespace>