remove v13 tests

Author: devsnek

.github/workflows/test.yml

@@ -6,9 +6,9 @@ jobs:
   test:
     strategy:
       matrix:
-        # TODO: add windows
         os: [ubuntu-latest, macos-latest, windows-latest]
-        node: [10, 12, 13, 14]
+        # https://nodejs.org/en/about/releases/
+        node: [10, 12, 14]
     runs-on: ${{ matrix.os }}
     steps:
       # https://github.com/actions/checkout/issues/135