Merge pull request #144 from BnLG/d7c

Solve bug introduced in #136

Hello,
This PR solves a bug introduced in #136, during plugin installation :
2022-07-04 16:54:29,721 [28336] (ERROR) (provd.app): Error while loading plugin wazo-snom-10.1.101.11
Traceback (most recent call last):
  File "/usr/lib/python2.7/dist-packages/provd/app.py", line 824, in _pg_load
    self.pg_mgr.load(id, gen_cfg, spec_cfg)
  File "/usr/lib/python2.7/dist-packages/provd/plugins.py", line 1134, in load
    plugin = obj(self._app, plugin_dir, gen_cfg, spec_cfg)
  File "/var/lib/wazo-provd/plugins/wazo-snom-10.1.101.11/common.py", line 153, in __init__
    fetchfw_helper = FetchfwPluginHelper(plugin_dir, downloaders)
  File "/usr/lib/python2.7/dist-packages/provd/plugins.py", line 554, in __init__
    self._pkg_mgr = self._new_pkg_mgr(downloaders, filter_builder)
  File "/usr/lib/python2.7/dist-packages/provd/plugins.py", line 572, in _new_pkg_mgr
    pkg_builder)
  File "/usr/lib/python2.7/dist-packages/xivo_fetchfw/storage.py", line 386, in __init__
    self._load_pkgs()
  File "/usr/lib/python2.7/dist-packages/xivo_fetchfw/storage.py", line 393, in _load_pkgs
    self._pkgs = self._create_pkg(config, pkg_sections, remote_files, install_mgr_factories)
  File "/usr/lib/python2.7/dist-packages/xivo_fetchfw/storage.py", line 455, in _create_pkg
    pkg = self._pkg_builder.build_installable_pkg(config, section, pkg_id, remote_files, install_mgr_factories)
  File "/usr/lib/python2.7/dist-packages/xivo_fetchfw/storage.py", line 280, in build_installable_pkg
    pkg_install_mgr = install_mgr_factory.new_install_mgr(src_node, local_vars)
  File "/usr/lib/python2.7/dist-packages/xivo_fetchfw/storage.py", line 188, in new_install_mgr
    filter_obj = self._filter_builder.build_node(tokens)
  File "/usr/lib/python2.7/dist-packages/xivo_fetchfw/storage.py", line 144, in build_node
    raise ValueError("unknown node type %s" % type)
ValueError: unknown node type touch

We finally do not need touch command, as cp command right above already modifies the modification date of the file, which is what we want here, perfect.
Thank you, and sorry for the inconveniences...

Reviewed-by: Alexandre Fournier <None>