Remove unnecessary dependency (#73)

Author: timothycoleman

test/EventStore.Plugins.Tests/EventStore.Plugins.Tests.csproj

@@ -21,7 +21,6 @@
 		  <PrivateAssets>all</PrivateAssets>
 		  <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
 		</PackageReference>
-		<PackageReference Include="System.Diagnostics.DiagnosticSource" Version="9.0.2" />
 		<PackageReference Include="xunit" Version="2.9.3" />
 		<PackageReference Include="xunit.runner.visualstudio" Version="3.0.2">
 		  <PrivateAssets>all</PrivateAssets>