chore: upgrade geth 1.9.19 -> 1.9.20 (#689)

Author: kilrau

images/geth/src.py

@@ -7,6 +7,6 @@ def __init__(self):
 
     def get_ref(self, version):
         if version == "latest":
-            return "v1.9.19"
+            return "v1.9.20"
         else:
             return super().get_ref(version)

images/utils/launcher/config/template.py

@@ -390,7 +390,7 @@ def __eq__(self, other):
         },
         "geth": {
             "name": "geth",
-            "image": "exchangeunion/geth:1.9.19",
+            "image": "exchangeunion/geth:1.9.20",
             "volumes": [
                 {
                     "host": "$data_dir/geth",