Revert "Revert "Avoid initializing Prometheus client in __init__().""
Revert "Revert "Avoid initializing Prometheus client in __init__().""

This reverts commit d532928fc62fdc3d1b751790e7a2acd908012c4d.

anarkiwi/faucet,gizmoguy/faucet,faucetsdn/faucet,REANNZ/faucet,gizmoguy/faucet,shivarammysore/faucet,trungdtbk/faucet,mwutzke/faucet,trentindav/faucet,wackerly/faucet,shivarammysore/faucet,REANNZ/faucet,mwutzke/faucet,faucetsdn/faucet,trungdtbk/faucet,anarkiwi/faucet,trentindav/faucet,wackerly/faucet