fix: update CI to test against Mendix 11.9.0

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: ako

.github/workflows/nightly.yml

@@ -14,7 +14,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        mendix-version: ['10.24.16.96987', '11.6.4', '11.8.0']
+        mendix-version: ['10.24.16.96987', '11.6.4', '11.9.0']
       fail-fast: false
     name: test (Mendix ${{ matrix.mendix-version }})
     steps:

.github/workflows/push-test.yml

@@ -18,7 +18,7 @@ jobs:
       - name: Test
         run: make test
       - name: Setup mxbuild
-        run: ./bin/mxcli setup mxbuild --version 11.8.0
+        run: ./bin/mxcli setup mxbuild --version 11.9.0
       - name: Integration tests
         run: make test-integration
         timeout-minutes: 30