chore(dockerfile): update tagfilter for jenkins/ssh-agent to enforce versioning (#1138)

Author: gounthar

updatecli/updatecli.d/ssh-agent.yaml

@@ -19,10 +19,11 @@ sources:
     kind: dockerimage
     spec:
       image: jenkins/ssh-agent
-      tagfilter: ^\d*(\.\d*){2}$
+      # Use \d+ to ensure major, minor, patch are present
+      tagfilter: ^\d+\.\d+\.\d+-jdk21$
       versionfilter:
         kind: semver
-        pattern: '>=5.20.0'
+        pattern: '>=0.0.0-0'
 
 targets:
   jenkins/python-agent: