Add new templates for vapor/penny-bot#81 (#867)

Adds new leaf templates that can be used with vapor/penny-bot#81.

We should not remove the old templates for now, until Penny has shown
some success.

.github/translation_needed.description.leaf

@@ -0,0 +1,14 @@
+The docs have been updated in PR ##(number). The translations should be updated if required.
+
+Languages:
+- [ ] English
+- [ ] Chinese
+- [ ] German
+- [ ] Dutch
+- [ ] Italian
+- [ ] Spanish
+- [ ] Polish
+- [ ] Korean
+
+Assigned to @vapor/translators - please submit a PR with the relevant updates and check the box once merged. 
+Please ensure you tag your PR with the `translation-update` so it doesn't create a new issue!

README.md

@@ -69,7 +69,7 @@ You can check it out by running `mkdocs serve` in the terminal. Once you are sat
 
 > NOTE: If a file isn't translated, it will just default to the default language file. So you don't have to translate everything all at once.
 
-Finally, you should add the new language to the [issue template](https://github.com/vapor/docs/blob/main/.github/workflows/translation-issue-template.md) to ensure that any future changes are applied to the new translation and to the [search index script](https://github.com/vapor/docs/blob/main/fixSearchIndex.swift) to ensure search works correctly.
+Finally, you should add the new language to the [issue template](https://github.com/vapor/docs/blob/main/.github/translation_needed.description.leaf) to ensure that any future changes are applied to the new translation and to the [search index script](https://github.com/vapor/docs/blob/main/fixSearchIndex.swift) to ensure search works correctly.