test: Fix errors that appeared after releasing new pylint

Author: p12tic

config/pylintrc

@@ -63,6 +63,7 @@ disable=
   missing-docstring,
   too-many-lines,
   no-self-use,
+  chained-comparison,
   duplicate-code,
   too-many-ancestors,
   too-many-instance-attributes,

ddg_parse_html.py

@@ -111,8 +111,7 @@ def get_declarations(root_el, name):
     if len(dcls) == 0:
         if not ignored:
             raise DdgException("dcl table contains no declarations")
-        else:
-            raise DdgException("All entries in dcl table were ignored")
+        raise DdgException("All entries in dcl table were ignored")
 
     return dcls