Arvados

1. ruby 2.6 and onward has bundler as part of the standard library. This means Ruby 2.5 and 2.6+ behave differently.
2. When you run bin/rails and it does require 'bundler/setup' it uses Ruby's built-in bundler.
3. Ruby's built in bundler finds the "BUNDLED WITH" line and adds a dependency on bundler 2.2.19
4. It tries to find "bundler 2.2.19" gem
5. It can't find it. I don't know why because it's definitely installed.

Running "arvbox restart dev" it's differently broken:

2022-02-17_22:18:39.12489 /var/lib/arvados/lib/ruby/gems/2.7.0/gems/bundler-2.2.19/lib/bundler/version.rb:4: warning: already initialized constant Bundler::VERSION
2022-02-17_22:18:39.12492 /var/lib/arvados-arvbox/.gem/ruby/2.7.0/gems/bundler-2.2.19/lib/bundler/version.rb:4: warning: previous definition of VERSION was here