Remove sample rsa key and add small README to point to Cluster Auditor BigBang repo

Dockerfile

@@ -30,5 +30,5 @@ RUN gem install --force --local -N /tmp/ffi.gem
 RUN gem install --force --local -N /tmp/*.gem
 
 RUN yum remove -y make gcc gcc-c++
-
+RUN rm -f /usr/local/bundle/gems/kubeclient-4.6.0/test/config/external-key.rsa
 USER fluent

README.md

-# master-project-template
+# OPA Collector
+
+This image is used as part of [Big Bang Cluster Auditor](https://repo1.dsop.io/platform-one/big-bang/apps/core/cluster-auditor) to collect Kubernetes object information to insert into Elasticsearch.
 
-Project template for all Iron Bank container repositories.
\ No newline at end of file