use %(...) and %[...] in favor of %<...>

app/helpers/blob_helper.rb

 module BlobHelper
   def highlight(blob_name, blob_content, repository: nil, plain: false)
     highlighted = Gitlab::Highlight.highlight(blob_name, blob_content, plain: plain, repository: repository)
-    raw %<<pre class="code highlight"><code>#{highlighted}</code></pre>>
+    raw %(<pre class="code highlight"><code>#{highlighted}</code></pre>)
   end
 
   def no_highlight_files

lib/banzai/filter/syntax_highlight_filter.rb

@@ -25,9 +25,9 @@ module Banzai
 
         begin
           highlighted = ''
-          highlighted << %<<pre class="#{css_classes}"><code>>
+          highlighted << %(<pre class="#{css_classes}"><code>)
           highlighted << formatter.format(lexer.lex(code))
-          highlighted << %<</code></pre>>
+          highlighted << %(</code></pre>)
         rescue
           # Gracefully handle syntax highlighter bugs/errors to ensure
           # users can still access an issue/comment/etc.

lib/rouge/formatters/html_gitlab.rb

@@ -17,9 +17,9 @@ module Rouge
           yield "\n" unless is_first
           is_first = false
 
-          yield %<<span id="LC#{@line_number}" class="line">>
+          yield %(<span id="LC#{@line_number}" class="line">)
           line.each { |token, value| yield span(token, value) }
-          yield %<</span>>
+          yield %(</span>)
 
           @line_number += 1
         end

spec/helpers/blob_helper_spec.rb

@@ -17,7 +17,7 @@ describe BlobHelper do
   describe '#highlight' do
     it 'should return plaintext for unknown lexer context' do
       result = helper.highlight(blob_name, no_context_content)
-      expect(result).to eq(%<<pre class="code highlight"><code><span id="LC1" class="line">:type "assem"))</span></code></pre>>)
+      expect(result).to eq(%[<pre class="code highlight"><code><span id="LC1" class="line">:type "assem"))</span></code></pre>])
     end
 
     it 'should highlight single block' do