Require that RubyGems accounts have MFA enabled for the user account

[jrgriffiniii]

There should be documentation for this, directing to https://guides.rubygems.org/setting-up-multifactor-authentication/. Further, this shall also require that the Gemspec files be updated for each component:

• [ ] active_fedora (https://github.com/samvera/active_fedora/issues/1481)
• [ ] bixby (https://github.com/samvera/bixby/issues/79)
• [ ] browse-everything (https://github.com/samvera/browse-everything/issues/388)
• [ ] hydra-derivatives (https://github.com/samvera/hydra-derivatives/issues/240)
• [ ] hydra-editor (https://github.com/samvera/hydra-editor/issues/209)
• [ ] hydra-file_characterization (https://github.com/samvera/hydra-file_characterization/issues/64)
• [ ] hydra-head (https://github.com/samvera/hydra-head/issues/547)
• [ ] hydra-pcdm (https://github.com/samvera/hydra-pcdm/issues/289)
• [ ] hydra-role-management (https://github.com/samvera/hydra-role-management/issues/68)
• [ ] hydra-works (https://github.com/samvera/hydra-works/issues/387)
• [ ] hyrax (https://github.com/samvera/hyrax/issues/5753)
• [ ] iiif_manifest (https://github.com/samvera/iiif_manifest/issues/67)
• [ ] ldp (https://github.com/samvera/ldp/issues/142)
• [ ] noid-rails (https://github.com/samvera/noid-rails/issues/114)
• [ ] questioning_authority (https://github.com/samvera/questioning_authority/issues/356)
• [ ] rubydora (https://github.com/samvera/rubydora/issues/143)
• [x] valkyrie (https://github.com/samvera/valkyrie/issues/898)

[jrgriffiniii]

As noted by @dlpierce, this would require that an update be made to the Gemspec file, and then a new release published: https://guides.rubygems.org/mfa-requirement-opt-in/