added generic docker image for concourse tasks

concourse-tools/Dockerfile

@@ -0,0 +1,10 @@
+FROM ghcr.io/alphagov/paas/bosh-cli-v2:main
+
+ENV AWSCLI_VERSION "1.19.112"
+
+RUN apt-get update && apt-get install -y \
+  curl \
+  python3 \
+  python3-pip \
+  && pip3 install \
+    awscli==$AWSCLI_VERSION

concourse-tools/README.md

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+# Concourse Tools
+
+This image is for building a container to run concourse tasks, which require various tools including: bosh-cli, awscli and curl. It uses bosh-cli-v2 as a base image and installs awscli on top using pip, and curl using apt.
+
+## Build locally
+
+```
+$ cd concourse-tools
+$ docker build -t concourse-tools .
+```
+
+## Run
+
+```
+docker run -it concourse-tools /bin/bash -c "bosh --version"
+```