Fix pulling in dependency that is Ruby 3.2+

This dependency is only used while releasing the gem so it's fine to
have it around and not work on all Rubies, but we do need to make
it conditional on the `gems.rb` file otherwise we break earlier Rubies.

Author: ivoanjo

ruby/gems.rb

@@ -10,4 +10,4 @@
 gem "http", "~> 5.0" unless RUBY_VERSION < "2.5"
 gem "pry"
 gem "pry-byebug" unless RUBY_VERSION > "3.1"
-gem "rubygems-await"
+gem "rubygems-await" unless RUBY_VERSION < "3.1"