[github ci]: Disable Java 8 (potentially temprorary)

We currently run into
https://github.com/android-actions/setup-android/issues/378

.github/workflows/ci.yml

@@ -12,7 +12,7 @@ jobs:
     runs-on: ubuntu-22.04
     strategy:
       matrix:
-        java: [ 8, 11 ]
+        java: [ 11 ]
 
     steps:
       - name: Checkout