Pin dependency release-plan to 0.13.1

Author: renovate[bot]

package.json

@@ -93,7 +93,7 @@
     "nyc": "17.1.0",
     "prettier": "3.5.3",
     "qunit": "2.24.1",
-    "release-plan": "^0.13.1",
+    "release-plan": "0.13.1",
     "rsvp": "4.8.5",
     "sinon": "20.0.0",
     "stylelint": "16.20.0",