Remove WikiService#get_formatted_data RPC

This RPC has gone unused as far as I can see, so I'm removing it to
decrease the API surface for Gitaly.

app/models/project_wiki.rb

@@ -160,12 +160,6 @@ class ProjectWiki
     update_project_activity
   end
 
-  def page_formatted_data(page)
-    page_title, page_dir = page_title_and_dir(page.title)
-
-    wiki.page_formatted_data(title: page_title, dir: page_dir, version: page.version)
-  end
-
   def page_title_and_dir(title)
     return unless title
 

app/models/wiki_page.rb

@@ -112,11 +112,6 @@ class WikiPage
     wiki.page_title_and_dir(slug)&.last.to_s
   end
 
-  # The processed/formatted content of this page.
-  def formatted_content
-    @attributes[:formatted_content] ||= @wiki.page_formatted_data(@page)
-  end
-
   # The markup format for the page.
   def format
     @attributes[:format] || :markdown

lib/gitlab/git/wiki.rb

@@ -133,14 +133,6 @@ module Gitlab
         GollumSlug.generate(title, format)
       end
 
-      def page_formatted_data(title:, dir: nil, version: nil)
-        version = version&.id
-
-        wrapped_gitaly_errors do
-          gitaly_wiki_client.get_formatted_data(title: title, dir: dir, version: version)
-        end
-      end
-
       private
 
       def gitaly_wiki_client

lib/gitlab/gitaly_client/wiki_service.rb

@@ -179,18 +179,6 @@ module Gitlab
         wiki_file
       end
 
-      def get_formatted_data(title:, dir: nil, version: nil)
-        request = Gitaly::WikiGetFormattedDataRequest.new(
-          repository: @gitaly_repo,
-          title: encode_binary(title),
-          revision: encode_binary(version),
-          directory: encode_binary(dir)
-        )
-
-        response = GitalyClient.call(@repository.storage, :wiki_service, :wiki_get_formatted_data, request, timeout: GitalyClient.medium_timeout)
-        response.reduce([]) { |memo, msg| memo << msg.data }.join
-      end
-
       private
 
       # If a block is given and the yielded value is truthy, iteration will be

spec/models/wiki_page_spec.rb

@@ -563,17 +563,6 @@ describe WikiPage do
     end
   end
 
-  describe '#formatted_content' do
-    it 'returns processed content of the page' do
-      subject.create({ title: "RDoc", content: "*bold*", format: "rdoc" })
-      page = wiki.find_page('RDoc')
-
-      expect(page.formatted_content).to eq("\n<p><strong>bold</strong></p>\n")
-
-      destroy_page('RDoc')
-    end
-  end
-
   describe '#hook_attrs' do
     it 'adds absolute urls for images in the content' do
       create_page("test page", "test![WikiPage_Image](/uploads/abc/WikiPage_Image.png)")