update go proxy 1.21@1.23.0 (#157)

core/java8actionloop/Dockerfile

diff --git a/core/java8actionloop/Dockerfile b/core/java8actionloop/Dockerfile
index d6c5c7e..53fbdc2 100644
--- a/core/java8actionloop/Dockerfile
+++ b/core/java8actionloop/Dockerfile
@@ -16,7 +16,7 @@
 #
 
 # build go proxy from source
-FROM golang:1.20 AS builder_source
+FROM golang:1.21 AS builder_source
 ARG GO_PROXY_GITHUB_USER=apache
 ARG GO_PROXY_GITHUB_BRANCH=master
 RUN git clone --branch ${GO_PROXY_GITHUB_BRANCH} \
@@ -25,8 +25,8 @@
    mv proxy /bin/proxy
 
 # or build it from a release
-FROM golang:1.20 AS builder_release
-ARG GO_PROXY_RELEASE_VERSION=1.20@1.22.0
+FROM golang:1.21 AS builder_release
+ARG GO_PROXY_RELEASE_VERSION=1.21@1.23.0
 RUN curl -sL \
   https://github.com/apache/openwhisk-runtime-go/archive/{$GO_PROXY_RELEASE_VERSION}.tar.gz\
   | tar xzf -\