request #7170: prevent make less to compile node_modules

whenever I run make less, it compiles .less files that should not be
compiled:
- node_modules when you use npm
- vendor when you use bower
- angular when your ng application have components with less files

Change-Id: Ia8b7454828cf04056488a937150e98c351fc75e0
Merge commit 'refs/changes/36/2736/1' of ssh://gerrit.tuleap.net:29418/tuleap into HEAD

* ssh://gerrit.tuleap.net:29418/tuleap:
  request #7170: prevent make less to compile node_modules

Change-Id: If3d8bfe63b6267f0d03dfecfeb518e721e0f60db
This is Tuleap 7.2.99.26

Change-Id: Idf5dc4c597cb8d8ab6fdfe0cb27f8863e29d9203