FIX: allow plugin pinning to fetch missing commits

Add update for fetching git commits if they do not exist, eg with
clone --depth 1 - only can fetch via git fetch --depth 1 {remote} {ref}
the ref needs to be a full, non-ambiguous reference.

lib/tasks/plugin.rake

@@ -120,7 +120,7 @@ task 'plugin:pull_compatible', :plugin do |t, args|
   # Checkout value of the version compat
   if checkout_version
     puts "checking out compatible #{plugin} version: #{checkout_version}"
-    update_status = system("git -C '#{plugin_path}' reset --hard #{checkout_version}")
+    update_status = system("git -C '#{plugin_path}' cat-file -e #{checkout_version} || git -C '#{plugin_path}' fetch --depth 1 $(git -C '#{plugin_path}' rev-parse --symbolic-full-name @{upstream} | awk -F '/' '{print $3}') #{checkout_version}; git -C '#{plugin_path}' reset --hard #{checkout_version}")
     abort('Unable to checkout a compatible plugin version') unless update_status
   else
     puts "#{plugin} is already at latest compatible version"

lib/theme_store/git_importer.rb

@@ -25,8 +25,7 @@ def import!
     end
     if version = Discourse.find_compatible_git_resource(@temp_folder)
       Discourse::Utils.execute_command(chdir: @temp_folder) do |runner|
-        Rails.logger.warn "git reset --hard #{version}"
-        return runner.exec("git", "reset", "--hard", version)
+        return runner.exec("git cat-file -e #{version} || git fetch --depth 1 $(git rev-parse --symbolic-full-name @{upstream} | awk -F '/' '{print $3}') #{version}; git reset --hard #{version}")
       end
     end
   end