Windows CI: add JDK 17 (alongside 8)

Author: SethTisue

.github/workflows/ci.yml

@@ -14,6 +14,10 @@ jobs:
     runs-on: windows-latest
     strategy:
       fail-fast: false
+      matrix:
+        include:
+          - java: 8
+          - java: 17-ea
     steps:
       - run: git config --global core.autocrlf false
       - name: Checkout
@@ -26,7 +30,7 @@ jobs:
         uses: actions/setup-java@v2
         with:
           distribution: adopt
-          java-version: 8
+          java-version: ${{matrix.java}}
 
       - name: Cache
         uses: actions/cache@v2