Add dynamodb client and refactor usages of json file from scripts

[VKong6019]

Issue: https://github.com/sandboxnu/boba-buddies/issues/29

HI i took the liberty in adding AWS sdk to include the DynamoDB client and refactor some usages of the pairings.json file from the manual scripts. Most of the logic for interacting with the DynamoDB tables we have are in the usersDataManager.ts and pairsDataManager.ts that pretty much includes some basic CRUD methods.

• the user manager will interact with a DynamoDB table - boba-buddies-users - that tracks the current list of members in the boba-buddies channel.
• the pairs manager will interact with a DynamoDB table - boba-buddies-pairs - that tracks the current list of channel ids and pairings from the boba-buddies channel.

~IMPORTANT: the refactoring part hasn't been tested yet so I will need to do that tomorrow and this will be fully ready for review~

[VKong6019]

cool beans, i just tested it with the scripts and fix some bugs. i think it should be good to go after review!