check_slow_queries_digest_result: threshold are floats

this program was comparing floats parsed from the report text and strings from
arguments passed on the command line, so basically it was not doing what was
intended.

slapos/promise/check_slow_queries_digest_result/__init__.py

@@ -71,8 +71,8 @@ def main():
   parser = argparse.ArgumentParser()
   parser.add_argument("--ptdigest_path", required=True)
   parser.add_argument("--status_file", required=True)
-  parser.add_argument("--max_queries_threshold", required=True)
-  parser.add_argument("--slowest_query_threshold", required=True)
+  parser.add_argument("--max_queries_threshold", required=True, type=float)
+  parser.add_argument("--slowest_query_threshold", required=True, type=float)
   args = parser.parse_args()
 
   status, message = checkMariadbDigestResult(args.ptdigest_path, args.status_file,