Fix script to make new versioned docs (#892)

This script was written to consider the root README as the source
of truth but I think that was before we realized that the docs
for the site have slightly different linking requirements.

As a result, the appropriate place to take the README from is the
master docs.

Fixes #887

Signed-off-by: John Schnake <jschnake@vmware.com>

scripts/update_docs.sh

@@ -63,7 +63,6 @@ else
         /bin/sh -c \
         "rm -rf /root/site/docs/${VERSION} && \
         cp -r /root/site/docs/master /root/site/docs/${VERSION} && \
-        cp /root/README.md /root/site/docs/${VERSION}/README.md && \
         sed -i 's/site\/docs\/master\///g' /root/site/docs/${VERSION}/README.md && \
         sed -i 's/docs\/img/img/g' /root/site/docs/${VERSION}/README.md && \
         sed -i 's/sonobuoy\/tree\/master/sonobuoy\/tree\/${VERSION}/g' /root/site/docs/${VERSION}/README.md && \