Update site documentation

Signed-off-by: Andrew Shirley <andrew.shirley@sainsburys.co.uk>
Signed-off-by: blam <ben@blam.sh>

docs/features/software-catalog/well-known-annotations.md

@@ -101,18 +101,22 @@ repository itself. If the URL points to a folder, it is important that it is
 suffixed with a `'/'` in order for relative path resolution to work
 consistently.
 
-### jenkins.io/github-folder
+### jenkins.io/folder-slug
 
 ```yaml
 # Example:
 metadata:
   annotations:
-    jenkins.io/github-folder: folder-name/job-name
+    jenkins.io/folder-slug: folder-name/job-name
 ```
 
 The value of this annotation is the path to a job on Jenkins, that builds this
 entity.
 
+The value can be the format of just `[folder-path]` or
+`[instanceName]:[folder-path]`, if multiple instances are configured in
+`app-config.yaml`
+
 Specifying this annotation may enable Jenkins related features in Backstage for
 that entity.
 
@@ -304,6 +308,10 @@ This annotation allowed to load the API definition from another location. Use
 [substitution](./descriptor-format.md#substitutions-in-the-descriptor-format)
 instead.
 
+### jenkins.io/github-folder
+
+Use the `jenkins.io/folder-slug` instead.
+
 ## Links
 
 - [Descriptor Format: annotations](descriptor-format.md#annotations-optional)