[rubygems/rubygems] Remove redundant part of error message

It doesn't really add much, in my opinion. We want to be helpful, but
also concise when possible.

https://github.com/rubygems/rubygems/commit/9d56009cf7

lib/bundler/resolver.rb

@@ -273,11 +273,7 @@ module Bundler
           specs = source.specs.search(name)
           versions_with_platforms = specs.map {|s| [s.version, s.platform] }
           message = String.new("Could not find gem '#{SharedHelpers.pretty_dependency(requirement)}' in #{source}#{cache_message}.\n")
-          message << if versions_with_platforms.any?
-            "The source contains the following versions of '#{name}': #{formatted_versions_with_platforms(versions_with_platforms)}"
-          else
-            "The source does not contain any versions of '#{name}'"
-          end
+          message << "The source contains the following versions of '#{name}': #{formatted_versions_with_platforms(versions_with_platforms)}" if versions_with_platforms.any?
         else
           message = "Could not find gem '#{SharedHelpers.pretty_dependency(requirement)}' in any of the gem sources " \
             "listed in your Gemfile#{cache_message}."

spec/bundler/commands/post_bundle_message_spec.rb

@@ -121,7 +121,6 @@ RSpec.describe "post bundle message" do
         G
         expect(err).to include <<-EOS.strip
 Could not find gem 'not-a-gem' in rubygems repository #{file_uri_for(gem_repo1)}/ or installed locally.
-The source does not contain any versions of 'not-a-gem'
         EOS
       end
 

spec/bundler/install/gemfile/sources_spec.rb

@@ -347,7 +347,6 @@ RSpec.describe "bundle install with gems on multiple sources" do
       it "fails" do
         bundle :install, :artifice => "compact_index", :raise_on_error => false
         expect(err).to include("Could not find gem 'private_gem_1' in rubygems repository https://gem.repo2/ or installed locally.")
-        expect(err).to include("The source does not contain any versions of 'private_gem_1'")
       end
     end
 

test/rubygems/test_gem.rb

@@ -1960,7 +1960,6 @@ class TestGem < Gem::TestCase
 
     expected = <<-EXPECTED
 Could not find gem 'a' in locally installed gems.
-The source does not contain any versions of 'a'
 You may need to `gem install -g` to install missing gems
 
     EXPECTED