Upgrade fastavro to 1.7.3 (#110)

Author: BewareMyPower

setup.py

@@ -90,7 +90,7 @@ def build_extension(self, ext):
 # avro dependencies
 extras_require["avro"] = sorted(
     {
-      "fastavro==0.24.0"
+      "fastavro==1.7.3"
     }
 )