ci: remove 14.x from ci

Author: brettstack

.github/workflows/release-on-push-to-mainline.yml

@@ -14,7 +14,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        node-version: [14.x, 16.x, 18.x, 20.x]
+        node-version: [16.x, 18.x, 20.x]
     steps:
       - name: Checkout
         uses: actions/checkout@v2