Handle CR-LFs properly in .gitmodules file

Any submodule lines that had a CR-LF ending would be ignored by the parser.

Closes gitlab-org/gitlab-ce#2262

lib/gitlab/git/gitmodules_parser.rb

@@ -46,6 +46,8 @@ module Gitlab
         iterator = State.new
 
         @content.split("\n").each_with_object(iterator) do |text, iterator|
+          text.chomp!
+
           next if text =~ /^\s*#/
 
           if text =~ /\A\[submodule "(?<name>[^"]+)"\]\z/
@@ -55,7 +57,7 @@ module Gitlab
 
             next unless text =~ /\A\s*(?<key>\w+)\s*=\s*(?<value>.*)\z/
 
-            value = $~[:value].chomp
+            value = $~[:value]
             iterator.set_attribute($~[:key], value)
           end
         end

spec/lib/gitlab/git/gitmodules_parser_spec.rb

@@ -2,7 +2,7 @@ require 'spec_helper'
 
 describe Gitlab::Git::GitmodulesParser do
   it 'should parse a .gitmodules file correctly' do
-    parser = described_class.new(<<-'GITMODULES'.strip_heredoc)
+    data = <<~GITMODULES
       [submodule "vendor/libgit2"]
          path = vendor/libgit2
       [submodule "vendor/libgit2"]
@@ -16,6 +16,7 @@ describe Gitlab::Git::GitmodulesParser do
           url = https://example.com/another/project
     GITMODULES
 
+    parser = described_class.new(data.gsub("\n", "\r\n"))
     modules = parser.parse
 
     expect(modules).to eq({