test exposing ssh keys during docker build

nginx/Dockerfile

@@ -1,7 +1,7 @@
-
+ARG NGINX_BRANCH=vanilla
 FROM alpine:latest AS base
 
-FROM alpine:latest AS build
+FROM alpine:latest AS build_stage_1
 ARG NGINX_VERSION LIBRESSL_VERSION=4.1.0
 ENV NGINX_VERSION=${NGINX_VERSION}
 RUN --mount=type=cache,target=/var/cache/apk apk update
@@ -42,6 +42,8 @@ USER luser
 WORKDIR /home/luser
 
 #RUN git clone --depth 1 --branch v4.0.0 https://github.com/libressl/portable.git libressl
+#RUN git clone --depth 1 --branch v4.0.0 https://github.com/libressl/portable.git libressl
+#ADD --chown=luser:luser git@github.com:libressl/portable.git#v${LIBRESSL_VERSION} libressl
 ADD --chown=luser:luser https://cdn.openbsd.org/pub/OpenBSD/LibreSSL/libressl-${LIBRESSL_VERSION}.tar.gz libressl.tgz
 RUN tar -xzf libressl.tgz && mv libressl-${LIBRESSL_VERSION} libressl && rm libressl.tgz
 RUN mkdir -p libressl/build
@@ -55,7 +57,15 @@ RUN cmake -G Ninja -B libressl/build -S libressl \
 	-DBUILD_SHARED_LIBS=OFF
 RUN cmake --build libressl/build
 
+FROM build_stage_1 AS build_stage_2_vanilla
+ARG NGINX_VERSION
 ADD --chown=luser:luser https://github.com/nginx/nginx.git#release-${NGINX_VERSION} /nginx
+
+FROM build_stage_1 AS build_stage_2_woggioni
+ARG NGINX_VERSION
+ADD --chown=luser:luser git@github.com:woggioni/nginx.git#release-${NGINX_VERSION} /nginx
+
+FROM build_stage_2_${NGINX_BRANCH} AS build
 ADD --chown=luser:luser https://github.com/openresty/headers-more-nginx-module.git /ngx_headers_more
 ADD --chown=luser:luser https://github.com/google/ngx_brotli.git /ngx_brotli
 USER root