Bump version and update README for cost-model #5

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1. Bump Kubecost cost-model version
2. Reformat README
3. Edit Dockerfile to clean cache

We'll add renovate.json in a separate PR.

Dockerfile

@@ -2,12 +2,16 @@ ARG BASE_REGISTRY=registry1.dso.mil
 ARG BASE_IMAGE=ironbank/redhat/ubi/ubi8
 ARG BASE_TAG=8.6
 
-FROM kubecost1/cost-model:prod-1.93.1 as base 
+FROM kubecost1/cost-model:prod-1.93.2 as base 
 
 FROM ${BASE_REGISTRY}/${BASE_IMAGE}:${BASE_TAG}
 
 COPY --from=base /go/bin/app /go/bin/app
 
+RUN dnf update -y --nodocs && \
+    dnf clean all && \
+    rm -rf /var/cache/dnf
+
 USER 1001
 EXPOSE 9090