client: make Redis::Client#ensure_connected handle fork reconnects

If reconnect is enabled and ensure_connected is called in the forked child of
the process that established the connection, a reconnect attempt should be made;
handle this case like any other ConnectionError.

Author: yaauie

lib/redis/client.rb

@@ -307,7 +307,7 @@ def ensure_connected
         tries += 1
 
         yield
-      rescue ConnectionError
+      rescue ConnectionError, InheritedError
         disconnect
 
         if tries < 2 && @reconnect