Py3.6: Ignore requests package warning about chardet 5

needed until psf/requests#6240 is fixed

schema_salad/__init__.py

@@ -1,9 +1,14 @@
 """Salad is a schema language for describing JSON or YAML structured linked data documents"""
 
 import logging
+import sys
+import warnings
 
 __author__ = "peter.amstutz@curoverse.com"
 
 _logger = logging.getLogger("salad")
 _logger.addHandler(logging.StreamHandler())
 _logger.setLevel(logging.INFO)
+
+if sys.version_info < (3, 7):
+    warnings.filterwarnings("ignore", message="urllib3.*", module="requests")