github source should default to secure protocol

Bundler 2 switched to secure https here c2e81f8

Insecure protocols should be avoided to prevent MITM attacks.

Author: jasonkarns

lib/rubygems/request_set/gem_dependency_api.rb

@@ -214,7 +214,7 @@ def initialize(set, path)
     git_source :github do |repo_name|
       repo_name = "#{repo_name}/#{repo_name}" unless repo_name.include? "/"
 
-      "git://github.com/#{repo_name}.git"
+      "https://github.com/#{repo_name}.git"
     end
 
     git_source :bitbucket do |repo_name|

test/rubygems/test_gem_request_set_gem_dependency_api.rb

@@ -183,7 +183,7 @@ def test_gem_github
 
     assert_equal [dep("a")], @set.dependencies
 
-    assert_equal %w[git://github.com/example/repository.git master],
+    assert_equal %w[https://github.com/example/repository.git master],
                  @git_set.repositories["a"]
 
     expected = { "a" => Gem::Requirement.create("!") }
@@ -196,7 +196,7 @@ def test_gem_github_expand_path
 
     assert_equal [dep("a")], @set.dependencies
 
-    assert_equal %w[git://github.com/example/example.git master],
+    assert_equal %w[https://github.com/example/example.git master],
                  @git_set.repositories["a"]
 
     expected = { "a" => Gem::Requirement.create("!") }