Set packer plugin path, so that it works on any user

ips/Dockerfile

@@ -2,6 +2,8 @@ FROM hashicorp/packer:latest as packer
 FROM hashicorp/terraform:latest as terraform
 FROM alpine:latest
 
+ENV PACKER_PLUGIN_PATH="/packer-plugins"
+
 COPY --from=packer /bin/packer /bin/
 COPY --from=terraform /bin/terraform /bin/
 RUN apk add --no-cache ansible aws-cli bash curl curl-dev git github-cli go gpg gpg-agent jq make mysql-client netcat-openbsd openssh-client openssh-keygen python3 py3-pip py3-jmespath rsync sudo tar && \