fix: prevent relref double base-prefix in render-link (#920)

* Fix announcement relrefs and add doc

* Revert glossary inline relref example

* Fix relref links with subdirectory baseURL

Co-authored-by: Max Mehl <max.mehl@deutschebahn.com>

* Simplify relref base-prefix guard in render-link

---------

Co-authored-by: Max Mehl <max.mehl@deutschebahn.com>

docs/hugo.yaml

@@ -32,7 +32,7 @@ languages:
     params:
       banner:
         message: |
-          هگزترا **v0.11** منتشر شد! 🎉 [تازه‌ها را ببینید]({{% ref "blog/v0.11" %}})
+          هگزترا **v0.11** منتشر شد! 🎉 [تازه‌ها را ببینید]({{% relref "blog/v0.11" %}})
       page:
         contextMenu:
           links:
@@ -47,7 +47,7 @@ languages:
     params:
       banner:
         message: |
-          Hextra **v0.11** がリリースされました！🎉 [新着情報はこちら]({{% ref "blog/v0.11" %}})
+          Hextra **v0.11** がリリースされました！🎉 [新着情報はこちら]({{% relref "blog/v0.11" %}})
       page:
         contextMenu:
           links:
@@ -62,7 +62,7 @@ languages:
     params:
       banner:
         message: |
-          Hextra **v0.11** 发布啦！🎉 查看[更新内容]({{% ref "blog/v0.11" %}})
+          Hextra **v0.11** 发布啦！🎉 查看[更新内容]({{% relref "blog/v0.11" %}})
       page:
         contextMenu:
           links:
@@ -166,7 +166,7 @@ params:
   banner:
     key: 'announcement-v0.11'
     message: |
-      Hextra **v0.11** is here! 🎉 Discover [what's new]({{% ref "blog/v0.11" %}})
+      Hextra **v0.11** is here! 🎉 Discover [what's new]({{% relref "blog/v0.11" %}})
 
   navbar:
     displayTitle: true