Rename methods to add auto links to HTML

The name `safe_html_with_links` was confusing and could make you think
it takes care of making the HTML safe. So I've renamed it in a way that
makes it a bit more intuitive that it expects its input to be already
sanitized.

I've changed `text_with_links` as well so now the two method names
complement each other.

lib/tasks/proposals.rake

@@ -12,7 +12,7 @@ namespace :proposals do
       model.find_each do |resource|
         if resource.external_url.present?
           Globalize.with_locale(I18n.default_locale) do
-            new_description = "#{resource.description} <p>#{text_with_links(resource.external_url)}</p>"
+            new_description = "#{resource.description} <p>#{sanitize_and_auto_link(resource.external_url)}</p>"
             resource.description = new_description
             resource.external_url = ""
             resource.updated_at = Time.current