Ship the customizations as a Docker image

The Docker image is used in the initialization process, to copy
everything in the custom folder to the Gitea data dir (mounted as a
persistent volume). It is built using Packer and is based on the busybox
image, so we can use its minimalist shell system to copy files and set
permissions

script/build_customizations_image

@@ -0,0 +1,7 @@
+#!/usr/bin/env bash
+# fail fast
+set -e
+
+cd packer/
+packer build custom.json
+cd -

script/copy_customization

@@ -1,11 +0,0 @@
-#!/usr/bin/env bash
-
-for podname in $(kubectl get pods -l name=gitea-server -o json \
-  | jq -r '.items[].metadata.name'); do
-    for path in ./kubernetes/custom/*; do
-      echo "Copying ${path}..."
-      kubectl cp "${path}" "${podname}":"/data/gitea/"
-    done
-  # Fix permissions
-  kubectl exec "${podname}" -- chown -R 1000:1000 /data/gitea/
-  done