C#: enable buildless mode

Author: tamasvajk

csharp/tools/autobuild.cmd

@@ -1,4 +1,6 @@
 @echo off
 
+set CODEQL_EXTRACTOR_CSHARP_OPTION_BUILDLESS=true
+
 type NUL && "%CODEQL_EXTRACTOR_CSHARP_ROOT%/tools/%CODEQL_PLATFORM%/Semmle.Autobuild.CSharp.exe"
 exit /b %ERRORLEVEL%

csharp/tools/autobuild.sh

@@ -7,4 +7,6 @@ if [ "$CODEQL_PLATFORM" != "linux64" ] && [ "$CODEQL_PLATFORM" != "osx64" ] ; th
     exit 1
 fi
 
+export CODEQL_EXTRACTOR_CSHARP_OPTION_BUILDLESS=true
+
 "$CODEQL_EXTRACTOR_CSHARP_ROOT/tools/$CODEQL_PLATFORM/Semmle.Autobuild.CSharp" || exit $?