Improve dotnet command output

* Set DOTNET_NOLOGO=true to avoid useless welcome messages for continuous integration
* Set DOTNET_CLI_TELEMETRY_OPTOUT=true to opt out of telemetry (and maybe shave off a few ms)

Author: 0xced

.github/workflows/continuous-integration.yml

@@ -5,6 +5,8 @@ on: push
 env:
   Configuration: Release
   ContinuousIntegrationBuild: true
+  DOTNET_CLI_TELEMETRY_OPTOUT: true
+  DOTNET_NOLOGO: true
 
 jobs:
   package: