Switch on nullable references for Tgstation.Server.Host.Common

src/Tgstation.Server.Host.Common/DotnetHelper.cs

@@ -21,6 +21,9 @@ namespace Tgstation.Server.Host.Common
 		public static IEnumerable<string> GetPotentialDotnetPaths(bool isWindows)
 		{
 			var enviromentPath = Environment.GetEnvironmentVariable("PATH");
+			if (enviromentPath == null)
+				return Enumerable.Empty<string>();
+
 			var paths = enviromentPath.Split(';');
 
 			var exeName = "dotnet";

src/Tgstation.Server.Host.Common/Tgstation.Server.Host.Common.csproj

@@ -4,6 +4,7 @@
   <PropertyGroup>
     <TargetFrameworks>$(TgsFrameworkVersion);net2.0</TargetFrameworks>
     <Version>$(TgsCoreVersion)</Version>
+    <Nullable>enable</Nullable>
   </PropertyGroup>
 
 </Project>