[FlINK-36392] pass MAVEN_HOME as a build arg

Author: SamBarker

.github/workflows/ci.yml

@@ -167,7 +167,8 @@ jobs:
           export DOCKER_BUILDKIT=1
           eval $(minikube -p minikube docker-env)
           export JAVA_VERSION=${{ matrix.java-version }}
-          docker build --progress=plain --no-cache -f ./Dockerfile -t flink-kubernetes-operator:ci-latest --progress plain --build-arg JAVA_VERSION="${JAVA_VERSION:-11}" .
+          env
+          docker build --progress=plain --no-cache -f ./Dockerfile -t flink-kubernetes-operator:ci-latest --progress plain --build-arg JAVA_VERSION="${JAVA_VERSION:-11}" --build-arg MAVEN_HOME="${HOME}/.m2" .
           docker images
       - name: Start the operator
         run: |

Dockerfile

@@ -19,7 +19,7 @@
 ARG JAVA_VERSION=11
 FROM maven:3.8.8-eclipse-temurin-${JAVA_VERSION} AS build
 ARG SKIP_TESTS=true
-ARG MAVEN_HOME=${HOME:~}/.m2
+ARG MAVEN_HOME=${HOME}/.m2
 
 WORKDIR /app