Switch the license validator to use config_provider and have a test license

Fixes the broken tests currently which try (and fail) to read the license file

util/config/provider/testprovider.py

@@ -5,6 +5,18 @@ from util.config.provider.baseprovider import BaseProvider
 
 REAL_FILES = ['test/data/signing-private.gpg', 'test/data/signing-public.gpg']
 
+class TestLicense(object):
+  @property
+  def subscription(self):
+    return {}
+
+  @property
+  def is_expired(self):
+    return False
+
+  def validate(self, config):
+    pass
+
 class TestConfigProvider(BaseProvider):
   """ Implementation of the config provider for testing. Everything is kept in-memory instead on
       the real file system. """
@@ -58,6 +70,9 @@ class TestConfigProvider(BaseProvider):
   def requires_restart(self, app_config):
     return False
 
+  def get_license(self):
+    return TestLicense()
+
   def reset_for_test(self):
     self._config['SUPER_USERS'] = ['devtable']
     self.files = {}