Update the spec version on the website

Signed-off-by: Andrea Frittoli <[email protected]>

Author: afrittoli

config.toml

@@ -115,7 +115,7 @@ archived_version = false
 # The version number for the version of the docs represented in this doc set.
 # Used in the "version-banner" partial to display a version number for the
 # current doc set.
-version = "v0.4.1"
+version = "v0.5.0"
 
 # A link to latest version of the docs. Used in the "version-banner" partial to
 # point people to the main doc site.
@@ -128,6 +128,10 @@ url_latest_version = "https://cdevents.dev/docs"
   version = "latest"
   url = "https://cdevents.dev/docs"
 
+[[params.versions]]
+ version = "v0.4.1"
+ url = "https://github.com/cdevents/spec/tree/v0.4.1/spec.md"
+
 [[params.versions]]
  version = "v0.3.0"
  url = "https://github.com/cdevents/spec/tree/v0.3.0/spec.md"