Faucet cloudflare worker for prefunding bounty hunters' addresses

1. Some 3rd party service (for example ubiquity bot) sends a POST request with the address query param, for example: https://ubq-faucet.workers.dev/?address=0x01
2. Openzeppelin Defender Relay service prefunds the 0x01 address with some gas payment tokens (XDAI, ETH, etc...) if the following conditions are met:
   • wallet address exists in the ubiquity bot's DB (i.e. the wallet is registered by some bounty hunter)
   • this is the 1st issue solved by a bounty hunter (i.e. the registered wallet address hasn't got any permits)
   • wallet address has 0 gas tokens amount

1. Setup env variables in the .dev.vars file:

# Environment variables used for development build on `yarn start`

# openzeppelin defender relay API key
RELAY_KEY=
# openzeppeling defender relay secret
RELAY_SECRET=

# supabase DB URL
SUPABASE_URL=
# supabase DB secret key
SUPABASE_KEY=

# fund amount in wei
CLAIM_FEE=

2. Run yarn start to start a local cloudflare worker instance