[rubygems/rubygems] Remove ensure part in require

I've seen this error sometimes but never found it helpful, since the
culprit has never been thread/monitor related, so it just adds noise.

Right now I'm seeing an issue in CI where we seem to be crashing during
ensure and showing a weird backtrace:

```
#<Thread:0x000055821d7a73b8 /home/runner/work/rubygems/rubygems/lib/rubygems/request_set.rb:167 run> terminated with exception (report_on_exception is true):
/home/runner/work/rubygems/rubygems/lib/rubygems/platform.rb:141:in `==': undefined local variable or method `to_a' for false:FalseClass (NameError)
Did you mean?  to_s
	from /home/runner/work/rubygems/rubygems/lib/rubygems/core_ext/kernel_require.rb:168:in `!='
	from /home/runner/work/rubygems/rubygems/lib/rubygems/core_ext/kernel_require.rb:168:in `require'
	from /home/runner/work/rubygems/rubygems/lib/rubygems.rb:441:in `block in ensure_subdirectories'
	from /home/runner/work/rubygems/rubygems/lib/rubygems.rb:437:in `each'
	from /home/runner/work/rubygems/rubygems/lib/rubygems.rb:437:in `ensure_subdirectories'
	from /home/runner/work/rubygems/rubygems/lib/rubygems.rb:413:in `ensure_gem_subdirectories'
	from /home/runner/work/rubygems/rubygems/lib/rubygems/resolver/specification.rb:110:in `download'
	from /home/runner/work/rubygems/rubygems/lib/rubygems/request_set.rb:173:in `block (2 levels) in install'
```

Let's get this out of the picture in case that helps clarify the
culprit.

https://github.com/rubygems/rubygems/commit/87ce40b70e

0 files changed, 0 insertions, 0 deletions