dockerfile: reduce interval and env config

- bitcoind and cln reduce healthcheck time interval
- cln healthcheck no need to use switch case instead use VLS_NETWORK
Signed-off-by: Lakshya Singh <lakshay.singh1108@gmail.com>

docker-compose.regtest.yml

@@ -19,7 +19,6 @@ services:
     ports:
       - 19846:19846
     environment:
-      - BITCOIN_CHAIN=regtest
       - VLS_NETWORK=regtest
       - BITCOIND_RPC_URL=http://rpcuser:VLSsigner1@bitcoind:38332