Added missing requirement for tracspamfilter plugin.

Author: bmispelon

requirements.txt

@@ -7,6 +7,7 @@ libsass==0.23.0
 
 # Trac plugins
 https://trac.edgewall.org/browser/plugins/trunk/spam-filter?rev=17752&format=zip
+filelock==3.13.1  # required for running tracspamfilter.filters.bayes
 # TracXMLRPC from PyPI does not (yet) have a 1.2.0 release (compatible with Trac >=1.4)
 https://trac-hacks.org/browser/xmlrpcplugin/trunk?rev=18591&format=zip