pylint: fix consider-using-enumerate cases

Fix all cases of C0200 consider-using-enumerate.

Part of #270

Author: DifferentialOrange

tarantool/msgpack_ext/decimal.py

@@ -244,8 +244,7 @@ def encode(obj, _):
     bytes_reverted = bytearray()
 
     scale = 0
-    for i in range(len(str_repr)):
-        str_digit = str_repr[i]
+    for i, str_digit in enumerate(str_repr):
         if str_digit == '.':
             scale = len(str_repr) - i - 1
             break

test/suites/test_pool.py

@@ -57,8 +57,8 @@ def set_ro(self, srv, read_only):
     def set_cluster_ro(self, read_only_list):
         assert len(self.servers) == len(read_only_list)
 
-        for i in range(len(self.servers)):
-            self.set_ro(self.servers[i], read_only_list[i])
+        for i, server in enumerate(self.servers):
+            self.set_ro(server, read_only_list[i])
 
     def retry(self, func, count=5, timeout=0.5):
         for i in range(count):