Vendor securerandom in Bundler as well

It is loaded by `Fetcher` so in most case it's fine.

But if using `bundler/inline` and a gem need to be fetched,
`securerandom` will be loaded and cause a conflict.

Can be reproduced with:

```ruby
require 'bundler/inline'

gemfile do
  source 'https://rubygems.org'
  gem 'graphql', '~> 2.0'
  gem 'graphql-client', '~> 0.18'
end

require 'json'
require 'graphql/client'
require 'graphql/client/http'
```

Ref: rails/rails#52473 (comment)

Co-authored-by: Jean Boussier <[email protected]>

Author: deivid-rodriguez

Manifest.txt

@@ -283,6 +283,10 @@ bundler/lib/bundler/vendor/pub_grub/lib/pub_grub/version_constraint.rb
 bundler/lib/bundler/vendor/pub_grub/lib/pub_grub/version_range.rb
 bundler/lib/bundler/vendor/pub_grub/lib/pub_grub/version_solver.rb
 bundler/lib/bundler/vendor/pub_grub/lib/pub_grub/version_union.rb
+bundler/lib/bundler/vendor/securerandom/.document
+bundler/lib/bundler/vendor/securerandom/LICENSE.txt
+bundler/lib/bundler/vendor/securerandom/lib/random/formatter.rb
+bundler/lib/bundler/vendor/securerandom/lib/securerandom.rb
 bundler/lib/bundler/vendor/thor/.document
 bundler/lib/bundler/vendor/thor/LICENSE.md
 bundler/lib/bundler/vendor/thor/lib/thor.rb
@@ -344,6 +348,7 @@ bundler/lib/bundler/vendored_fileutils.rb
 bundler/lib/bundler/vendored_net_http.rb
 bundler/lib/bundler/vendored_persistent.rb
 bundler/lib/bundler/vendored_pub_grub.rb
+bundler/lib/bundler/vendored_securerandom.rb
 bundler/lib/bundler/vendored_thor.rb
 bundler/lib/bundler/vendored_timeout.rb
 bundler/lib/bundler/vendored_tsort.rb

bundler/lib/bundler/fetcher.rb

@@ -3,7 +3,7 @@
 require_relative "vendored_persistent"
 require_relative "vendored_timeout"
 require "cgi"
-require "securerandom"
+require_relative "vendored_securerandom"
 require "zlib"
 
 module Bundler
@@ -182,7 +182,7 @@ def user_agent
         agent << " ci/#{cis.join(",")}" if cis.any?
 
         # add a random ID so we can consolidate runs server-side
-        agent << " " << SecureRandom.hex(8)
+        agent << " " << Gem::SecureRandom.hex(8)
 
         # add any user agent strings set in the config
         extra_ua = Bundler.settings[:user_agent]

bundler/lib/bundler/vendor/securerandom/.document

@@ -0,0 +1 @@
+# Vendored files do not need to be documented

bundler/lib/bundler/vendor/securerandom/LICENSE.txt

@@ -0,0 +1,22 @@
+Copyright (C) 1993-2013 Yukihiro Matsumoto. All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions
+are met:
+1. Redistributions of source code must retain the above copyright
+notice, this list of conditions and the following disclaimer.
+2. Redistributions in binary form must reproduce the above copyright
+notice, this list of conditions and the following disclaimer in the
+documentation and/or other materials provided with the distribution.
+
+THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+SUCH DAMAGE.