ci(nightly): test against Mendix 11.12 instead of 11.11

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Author: ako

.github/workflows/nightly.yml

@@ -14,7 +14,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        mendix-version: ['10.24.19.104498', '11.6.6', '11.11.0']
+        mendix-version: ['10.24.19.104498', '11.6.6', '11.12.0']
       fail-fast: false
     name: test (Mendix ${{ matrix.mendix-version }})
     steps: