Add Performance category to the changelog

Resolves gitlab-org/gitlab-ce#36417

bin/changelog

@@ -28,6 +28,7 @@ class ChangelogOptionParser
     Type.new('deprecated', 'New deprecation'),
     Type.new('removed', 'Feature removal'),
     Type.new('security', 'Security fix'),
+    Type.new('performance', 'Performance improvement'),
     Type.new('other', 'Other')
   ].freeze
   TYPES_OFFSET = 1

changelogs/unreleased/zj-add-performance-changelog-cat.yml

@@ -0,0 +1,5 @@
+---
+title: Add Performance improvement as category on the changelog
+merge_request:
+author:
+type: performance

spec/bin/changelog_spec.rb

@@ -84,7 +84,7 @@ describe 'bin/changelog' do
           expect do
             expect do
               expect { described_class.read_type }.to raise_error(SystemExit)
-            end.to output("Invalid category index, please select an index between 1 and 7\n").to_stderr
+            end.to output("Invalid category index, please select an index between 1 and 8\n").to_stderr
           end.to output.to_stdout
         end
       end