Merge pull request #621 from admin-shell-io/BiBo/fix_dpp

Annex DPP: fix nav.adoc + update text

Author: BirgitBoss

documentation/IDTA-01002-3/modules/ROOT/nav.adoc

@@ -74,6 +74,8 @@ Shared .adoc file are used from https://github.com/admin-shell-io/aas-specs-meta
 
 ** xref:annex/serialization-modifier-examples.adoc[SerializationModifier Examples]
 
+** xref:annex/dpp.adoc[Digital Product Passport]
+
 ** xref:annex/backus-naur-form.adoc[Backus Naur Form]
 
 ** xref:annex/uml-templates.adoc[Class Table Templates]