docs: Redis add redis encrypted example (#25536)

Co-authored-by: Michael Kriese <michael.kriese@visualon.de>

docs/usage/self-hosted-configuration.md

@@ -761,8 +761,15 @@ Override this object if you want to change the URLs that Renovate links to, e.g.
 
 If this value is set then Renovate will use Redis for its global cache instead of the local file system.
 The global cache is used to store lookup results (e.g. dependency versions and release notes) between repositories and runs.
+
+For non encrypted connections,
+
 Example URL structure: `redis://[[username]:[password]]@localhost:6379/0`.
 
+For TLS/SSL-enabled connections, use rediss prefix
+
+Example URL structure: `rediss://[[username]:[password]]@localhost:6379/0`.
+
 ## repositories
 
 Elements in the `repositories` array can be an object if you wish to define more settings: