[token-server] Reduce faucet reward
Summary:
Some kind of script is going through the 30xec rewards. need to get some countermeasures together.
for starters, reduce the reward.
Test Plan: npm test
Reviewers: #bitcoin_abc, johnkuney
Reviewed By: #bitcoin_abc, johnkuney
Differential Revision: https://reviews.bitcoinabc.org/D16680