Use HTML beautifier to indent ERB files

We had inconsistent indentation in many places. Now we're fixing them
and adding a linter to our CI so we don't accidentally introduce
inconsistent indentations again.

app/views/shared/_author_info.html.erb

@@ -1,12 +1,12 @@
 <% if resource.author.hidden? || resource.author.erased? %>
   <span class="icon-deleted author-deleted"></span>
   <span class="author deleted">
-      <%= t("shared.author_info.author_deleted") %>
+    <%= t("shared.author_info.author_deleted") %>
   </span>
 <% else %>
   <%= render Shared::AvatarComponent.new(resource.author, size: 32, class: "author-photo") %>
   <span class="author">
-      <%= link_to resource.author.name, user_path(resource.author) %>
+    <%= link_to resource.author.name, user_path(resource.author) %>
   </span>
 
   <% if resource.respond_to?(:association_name) && resource.association_name.present? %>

app/views/shared/_filter_subnav.html.erb

@@ -3,7 +3,9 @@
 
   <% valid_filters.each do |filter| %>
     <% if current_filter == filter %>
-      <li class="is-active"><h2><%= t("#{i18n_namespace}.filters.#{filter}") %></h2></li>
+      <li class="is-active">
+        <h2><%= t("#{i18n_namespace}.filters.#{filter}") %></h2>
+      </li>
     <% else %>
       <li><%= link_to t("#{i18n_namespace}.filters.#{filter}"),
                       current_path_with_query_params(filter: filter, page: 1) %></li>