Bug: formideploy archives shouldn't require deploy validation.

[ryan-roemer]

For example, in formidable.com repo if we do formideploy archives in an uninstalled/non-built repo we get this:

[formideploy] Starting {"action":"archives"} with options {"port":5000,"limit":10,"start":"2021-04-06T14:49:38.241Z","dryrun":false,"production":false,"staging":false}
[formideploy][error] Error: Build output missing at: public
    at validate (/Users/rye/scm/fmd/formideploy/lib/config/index.js:210:11)
    at async archives (/Users/rye/scm/fmd/formideploy/lib/actions/archives.js:208:3)
    at async main (/Users/rye/scm/fmd/formideploy/bin/formideploy.js:95:3)