Change order of operations for anchor generation

lib/gitlab/utils/markdown.rb

@@ -4,13 +4,13 @@ module Gitlab
   module Utils
     module Markdown
       PUNCTUATION_REGEXP = /[^\p{Word}\- ]/u.freeze
-      PRODUCT_SUFFIX = /\((CORE|STARTER|PREMIUM|ULTIMATE)(\s+ONLY)?\)/.freeze
+      PRODUCT_SUFFIX = /\s*\((core|starter|premium|ultimate)(\s+only)?\)/.freeze
 
       def string_to_anchor(string)
         string
-          .gsub(PRODUCT_SUFFIX, '')
           .strip
           .downcase
+          .gsub(PRODUCT_SUFFIX, '')
           .gsub(PUNCTUATION_REGEXP, '') # remove punctuation
           .tr(' ', '-') # replace spaces with dash
           .squeeze('-') # replace multiple dashes with one

spec/lib/gitlab/utils/markdown_spec.rb

@@ -58,6 +58,14 @@ RSpec.describe Gitlab::Utils::Markdown do
       it 'ignores a product suffix' do
         is_expected.to eq 'my-header'
       end
+
+      context 'with only modifier' do
+        let(:string) { 'My Header (STARTER ONLY)' }
+
+        it 'ignores a product suffix' do
+          is_expected.to eq 'my-header'
+        end
+      end
     end
 
     context 'when string is empty' do