[mod] pylint: add extension-pkg-whitelist=lxml.etree

.pylintrc

@@ -12,7 +12,7 @@
 # A comma-separated list of package or module names from where C extensions may
 # be loaded. Extensions are loading into the active Python interpreter and may
 # run arbitrary code
-extension-pkg-whitelist=
+extension-pkg-whitelist=lxml.etree
 
 # Add files or directories to the blacklist. They should be base names, not
 # paths.