Remove Windows from the CI matrix to avoid infinite loop

Author: olafurpg

.github/workflows/ci.yml

@@ -9,7 +9,7 @@ jobs:
     runs-on:  ${{ matrix.os }}
     strategy:
       matrix:
-        os: [windows-latest, ubuntu-latest]
+        os: [ubuntu-latest]
     steps:
       - uses: actions/checkout@v2
       - uses: actions/setup-java@v1