[infra] Add experimental debian testing base image.

infra/base-images/base-image-debian-testing/Dockerfile

@@ -0,0 +1,16 @@
+FROM debian:testing
+
+ENV DEBIAN_FRONTEND noninteractive
+RUN echo 'deb-src http://deb.debian.org/debian testing main' >> /etc/apt/sources.list && \
+    apt-get update && \
+    apt-get upgrade -y && \
+    apt-get install -y libc6-dev binutils libgcc-7-dev && \
+    apt-get autoremove -y
+
+
+ENV OUT=/out
+ENV SRC=/src
+ENV WORK=/work
+ENV PATH="$PATH:/out"
+
+RUN mkdir -p $OUT $SRC $WORK && chmod a+rwx $OUT $SRC $WORK