Inside a wiki, when we show the sidebar or browse to the `pages`,
all page contents are retrieved from Gitaly and that is a waste
of resources, since no content from that pages are going to be
showed.
This MR introduces the method `ProjectWiki#list_pages`,
which uses new wiki_list_pages RPC call to retrieve
pages without content
Also in the `WikisController` we're using the method to show
pages in the sidebar and also on the `pages` page.
Inlining this code allows us to remove a dependency on gitlab_grit in
gitlab-ce. We can't stop maintaining gitlab_grit yet, since gitaly-ruby
still depends on this gem, but it moves us a step closer.
Without this parameter, every load of a Wiki page will load all the Wiki pages
in the repository for the sidebar. This is a significant performance penalty
that can significant slow the display of all Wiki pages.
Relates to #40101
GitLab Bot
Francisco Javier López
Nick Thomas
Stan Hu
Jacob Vosmaer (GitLab)