ci: add interesting jdks to matrix

Author: lread

.github/workflows/test.yml

@@ -16,7 +16,7 @@ jobs:
       fail-fast: false
       matrix:
         os: [ ubuntu ]
-        java-version: [ '23' ]
+        java-version: [ '8', '11', '17', '21', '23' ]
 
     name: test ${{matrix.os}} jdk${{matrix.java-version}}