CI: Remove unsupported Node.js versions

Author: Turbo87

.github/workflows/ci.yml

@@ -36,7 +36,7 @@ jobs:
   tests:
     strategy:
       matrix:
-        node-version: [12.x, 14.x, 16.x, 18.x, 20.x, 22.x]
+        node-version: [20.x, 22.x]
 
     name: Tests (Node.js ${{ matrix.node-version }})
     runs-on: ubuntu-latest