check json_post_data!none when sending ?q= (#800)

Author: pvgenuchten

pycsw/ogc/api/records.py

@@ -569,7 +569,8 @@ def items(self, headers_, json_post_data, args, collection='metadata:main',
                         if end != '..':
                             query_args.append(f'time_end <= "{end}"')
                 elif k == 'q':
-                    query_args.append(build_anytext('anytext', v))
+                    if v not in [None,'']:
+                        query_args.append(build_anytext('anytext', v))
                 else:
                     query_args.append(f'{k} = "{v}"')