This require causes circular require.
```
$ touch empty_file
$ RUBYGEMS_GEMDEPS=empty_file ./local/bin/ruby -w -e ''
/home/mame/work/ruby/local/lib/ruby/2.7.0/rubygems/core_ext/kernel_require.rb:92: warning: /home/mame/work/ruby/local/lib/ruby/2.7.0/rubygems/core_ext/kernel_require.rb:92: warning: loading in progress, circular require considered harmful - /home/mame/work/ruby/local/lib/ruby/2.7.0/rubygems.rb
from <internal:gem_prelude>:1:in `<internal:gem_prelude>'
from <internal:gem_prelude>:1:in `require'
from /home/mame/work/ruby/local/lib/ruby/2.7.0/rubygems.rb:1417:in `<top (required)>'
from /home/mame/work/ruby/local/lib/ruby/2.7.0/rubygems.rb:1203:in `use_gemdeps'
from /home/mame/work/ruby/local/lib/ruby/2.7.0/rubygems/user_interaction.rb:47:in `use_ui'
from /home/mame/work/ruby/local/lib/ruby/2.7.0/rubygems.rb:1204:in `block in use_gemdeps'
from /home/mame/work/ruby/local/lib/ruby/2.7.0/rubygems/core_ext/kernel_require.rb:92:in `require'
from /home/mame/work/ruby/local/lib/ruby/2.7.0/rubygems/core_ext/kernel_require.rb:92:in `require'
from /home/mame/work/ruby/local/lib/ruby/2.7.0/bundler.rb:11:in `<top (required)>'
from /home/mame/work/ruby/local/lib/ruby/2.7.0/bundler.rb:11:in `require_relative'
from /home/mame/work/ruby/local/lib/ruby/2.7.0/bundler/rubygems_integration.rb:3:in `<top (required)>'
from /home/mame/work/ruby/local/lib/ruby/2.7.0/rubygems/core_ext/kernel_require.rb:92:in `require'
from /home/mame/work/ruby/local/lib/ruby/2.7.0/rubygems/core_ext/kernel_require.rb:92:in `require'
```
https://github.com/bundler/bundler/commit/c7c5bcea92
75dca097b8