Update builder and base image references (#244)

* Update the builder imge reference, and the base image reference

Dockerfile

@@ -25,7 +25,7 @@
 # In order to create a consistent and verifiable the build environment, only add
 # or update in the mobilecoin/rust-sgx-base image and refer to the image by its hash.
 
-FROM mobilecoin/rust-sgx-base@sha256:cf4ff6d68e937d1f57a8e445a06e257949b515a241e06c32c41820ec697c2ddb as builder
+FROM mobilecoin/rust-sgx-base@sha256:a7fcad9b7172ea0f20b2a83a47fbc34f13363cfd95788cc32427a658790adef0 as builder
 
 ARG NAMESPACE=test
 ARG SIGNED_ENCLAVE_BASE=enclave-distribution.${NAMESPACE}.mobilecoin.com
@@ -61,7 +61,7 @@ RUN  --mount=type=cache,target=/root/.cargo/git \
 
 # This is the runtime container.
 # Adding/updating OS will not affect the ability to verify the build environment.
-FROM ubuntu:bionic-20210416
+FROM ubuntu:focal-20211006
 
 RUN  addgroup --system --gid 1000 app \
   && adduser --system --ingroup app --uid 1000 app \
@@ -89,4 +89,4 @@ ENV CONSENSUS_ENCLAVE_CSS=/usr/local/bin/consensus-enclave.css
 
 ENTRYPOINT ["/usr/local/bin/full-service", "--wallet-db=/data/wallet.db", "--ledger-db=/data/ledger.db", "--listen-host=0.0.0.0", "--fog-ingest-enclave-css=/usr/local/bin/ingest-enclave.css"]
 
-CMD [ "--help" ]
+CMD [ "--help" ]