chore: enable minor Dockerfile updates (#2723)

Co-authored-by: Armel Soro <armel@rm3l.org>

Author: kim-tsao

.github/renovate.json

@@ -89,15 +89,16 @@
       "automerge": false
     },
     {
-      "description": "Do NOT generate PRs for minor dockerfile updates in 1.y ",
-      "enabled": false,
+      "description": "Do generate PRs for minor dockerfile updates in 1.y ",
+      "enabled": true,
       "matchDatasources": [
         "docker"
       ],
       "matchUpdateTypes": [
         "minor"
       ],
       "matchBaseBranches": [
+        "main",
         "/^release-1\\..*/"
       ],
       "automerge": false