Update DoD Approved External PKI Certificate Trust Chains to Version 9.0

Per https://repo1.dso.mil/platform-one/big-bang/apps/developer-tools/gitlab/-/blob/main/chart/bigbang/README.md version 7.3 of the trust chains is currently included.

Version 9.0 is now available from https://public.cyber.mil/pki-pke/pkipke-document-library/:
https://dl.dod.cyber.mil/wp-content/uploads/pki-pke/zip/unclass-dod_approved_external_pkis_trust_chains.zip