Clean up unused components

[jesserockz]

After #100 We no longer need the i2s_audio folder as part of this repo.

The speaker override was also not being used, so clean that up too.

[github-actions[bot]]

Firmware built successfully! :tada:

Download and extract the firmware to install with https://web.esphome.io

Make sure to choose esphome-voice-kit-esp32s3/esphome-voice-kit-esp32s3.factory.bin.