build with latest jdk version (#20)

.github/workflows/main.yaml

@@ -29,11 +29,17 @@ jobs:
         java_version:
           - 17
           - 21
+          - 23
         include:
           - java_version: '17'
             mvn_opts: ''
+            experimental: false
           - java_version: '21'
             mvn_opts: ''
+            experimental: false
+          - java_version: '23'
+            mvn_opts: ''
+            experimental: true
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
@@ -58,11 +64,9 @@ jobs:
             ${{ matrix.mvn_opts }}
 
       - name: Integration test with JDK ${{ matrix.java_version }}
-        ## allow builds to run only:
-        ## - on the main branch when it is not a pull request,
-        ## - for pull requests from the same repository
-        ## - when triggered manually
-        if: (github.event_name == 'pull_request' && github.head_repo.full_name == github.repository) || (github.event_name == 'push' && github.ref == 'refs/heads/main') || github.event_name == 'workflow_dispatch'
+        ## The step or job will only run if the `experimental` variable
+        ## in the matrix is false (not set to true)
+        if: ${{ !matrix.experimental }}
         run: |
           mvn -B -U verify \
             -Dgib.disable=false -Dgib.referenceBranch=__branch_before \