fix(ext): allow loading chain_spec from config

cic/cmd/ext.py

@@ -10,7 +10,7 @@ from cic.contract.network import Network
 
 def process_args(argparser):
     argparser.add_argument(
-        "--registry", required=True, type=str, help="contract registry address"
+        "--registry", type=str, help="contract registry address"
     )
     argparser.add_argument(
         "-d", "--directory", type=str, dest="directory", default=".", help="directory"
@@ -28,11 +28,11 @@ def execute(config, eargs):
     cn = Network(eargs.directory, targets=eargs.target)
     cn.load()
 
-    chain_spec = ChainSpec.from_chain_str(eargs.i)
+    chain_spec = ChainSpec.from_chain_str(eargs.i or config.get("CHAIN_SPEC"))
     m = importlib.import_module(f"cic.ext.{eargs.target}.start")
     m.extension_start(
         cn,
-        registry_address=eargs.registry,
+        registry_address=eargs.registry or config.get("CIC_REGISTRY_ADDRESS"),
         chain_spec=chain_spec,
         rpc_provider=config.get("RPC_PROVIDER"),
-    )
+    ) # TODO add key account address