use latest stable act_runner release instead of nightly builds

build-image.sh

@@ -39,6 +39,7 @@ DOCKER_BUILDKIT=1 docker build "$project_root" \
    --build-arg GIT_COMMIT_DATE="$(date -d @$(git log -1 --format='%at') --utc +'%Y-%m-%d %H:%M:%S UTC')" \
    --build-arg GIT_COMMIT_HASH="$(git rev-parse --short HEAD)" \
    --build-arg GIT_REPO_URL="$(git config --get remote.origin.url)" \
+   --build-arg ACT_RUNNER_DOWNLOAD_URL=$(curl -sSfL https://gitea.com/gitea/act_runner/releases | grep -oP "https://gitea.com/gitea/act_runner/releases/download/.*-linux-amd64" | head -1) \
    -t $image_name \
    "$@"
 

image/Dockerfile

@@ -64,7 +64,7 @@ ARG DEBIAN_FRONTEND=noninteractive
 ARG LC_ALL=C
 ARG INSTALL_SUPPORT_TOOLS=0
 
-ARG ACT_RUNNER_DOWNLOAD_URL=https://dl.gitea.com/act_runner/main/act_runner-main-linux-amd64
+ARG ACT_RUNNER_DOWNLOAD_URL
 ARG UPX_COMPRESS=true
 
 RUN --mount=type=bind,source=.shared,target=/mnt/shared <<EOF