Fix: change caa_identities field to be optional in DirectoryMetadata#74

bavshin-f5 merged 1 commit intonginx:mainnginx/nginx-acme:mainfrom

mdegel:bugfix/73-caaIdentities-should-accept-nullmdegel/nginx-acme:bugfix/73-caaIdentities-should-accept-nullCopy head branch name to clipboard