adding testing for redis

lemur/tests/test_redis.py

@@ -0,0 +1,13 @@
+import fakeredis
+import time
+import sys
+
+
+def test_write_and_read_from_redis():
+    function = f"{__name__}.{sys._getframe().f_code.co_name}"
+
+    red = fakeredis.FakeStrictRedis()
+    key = f"{function}.last_success"
+    value = int(time.time())
+    assert red.set(key, value) is True
+    assert (int(red.get(key)) == value) is True