Removed node 13 from github workflow

.github/workflows/ci.yml

@@ -18,8 +18,6 @@ jobs:
         include:
           - os: ubuntu-latest,
             node-version: 12.x
-          - os: ubuntu-latest,
-            node-version: 13.x
           - os: ubuntu-latest,
             node-version: 14.x
           - os: ubuntu-latest,