Enable colored output in GitHub actions

See dotnet/runtime#68302

Author: 0xced

.github/workflows/continuous-integration.yml

@@ -8,6 +8,8 @@ env:
   DOTNET_CLI_TELEMETRY_OPTOUT: true
   DOTNET_NOLOGO: true
   DOTNET_SKIP_FIRST_TIME_EXPERIENCE: true
+  DOTNET_SYSTEM_CONSOLE_ALLOW_ANSI_COLOR_REDIRECTION: true
+  TERM: xterm
 
 jobs:
   package: