fix: unset ready on reconnect

[LordOfPolls]

What type of pull request is this?

• [x] Non-breaking code change
• [ ] Breaking code change
• [ ] Documentation change/addition
• [ ] Tests change

Description

Resolves #591 by unsetting ready during gateway reconnects

Changes

• Add new state method called clear_ready which clears the client ready state
• Gateway now calls clear_ready during reconnect attempts

Checklist

• [x] I've formatted my code with Black
• [x] I've ensured my code works on Python 3.10.x
• [x] I've tested my code