fix building protobuf when user name is not the same as primary group name

cmake_targets/tools/build_helper

@@ -210,7 +210,7 @@ install_protobuf_from_source(){
     #cd protobuf-2.6.1/
     rm -rf /tmp/protobuf-cpp-3.3.0.tar.gz* /tmp/protobuf-3.3.0
     wget https://github.com/google/protobuf/releases/download/v3.3.0/protobuf-cpp-3.3.0.tar.gz
-    tar -xzvf protobuf-cpp-3.3.0.tar.gz --owner $USER --group $USER --no-same-owner
+    tar -xzvf protobuf-cpp-3.3.0.tar.gz --owner $USER --group $(groups | cut -d" " -f1) --no-same-owner
     cd protobuf-3.3.0/
     ./configure
     echo "Compiling protobuf"