Remove Triton URL from repo / Link to QuickNode

[abunsen]

Thanks for building this tool! Noticed you were leaking your Triton credentials, so I updated to use the public good from QuickNode - JupiterAPI.com - did it for a couple reasons:

1. Remove your Triton credentials so other people can't run up your bill
2. Give users higher rate limits than the Jupiter hosted API

Note: JupiterAPI.com charges 20 bps per trade, it's how we continue to offer it for free.

I also linked to QuickNode's paid version of Jupiter Swap API in the README.

[abunsen]

cc @JunaidPeer