LINDEX command is incorrect

[brussell98]

Per https://redis.io/commands/lindex, LINDEX returns the element at the index in a list, or nil.

In this package LINDEX expects key, element and returns number, but per the Redis docs LINDEX should expect key, index and return string. Seems like the command was mistakenly written for LPUSH's logic.

Environment:

• Node.js Version: 16.13.0
• Redis Server Version: 5.0.14
• Node Redis Version: 4.0.0-rc.3
• Platform: Windows 10