Fix trailing whitespace

spec/lib/gitlab/file_detector_spec.rb

@@ -17,7 +17,7 @@ describe Gitlab::FileDetector do
     it 'returns the type of a README file' do
       filenames = Gitlab::MarkupHelper::PLAIN_FILENAMES + Gitlab::MarkupHelper::PLAIN_FILENAMES.map(&:upcase)
       extensions = Gitlab::MarkupHelper::EXTENSIONS + Gitlab::MarkupHelper::EXTENSIONS.map(&:upcase)
-      
+
       filenames.each do |filename|
         expect(described_class.type_of(filename)).to eq(:readme)
         extensions.each do |extname|