chore(ci): remove multi-node version matrix (#317)

* chore(ci): remove multi-node version matrix from branch CI

Since we only deploy Cloudflare Workers and don't publish npm packages,
testing across multiple Node versions is unnecessary. This aligns the
branch workflow with main.yml which already uses a single Node version.

* chore(ci): use latest LTS Node version

Use lts/* instead of hardcoding Node 22 so CI automatically picks up
new LTS releases.

* revert: keep Node 22 hardcoded in CI setup

Author: mattzcarey

.github/workflows/branches.yml

@@ -13,14 +13,9 @@ jobs:
     permissions:
       contents: read
     timeout-minutes: 10
-    strategy:
-      matrix:
-        node-version: [20, 22]
     steps:
       - uses: actions/checkout@v4
       - uses: ./.github/actions/setup
-        with:
-          node-version: ${{ matrix.node-version }}
 
       - name: Syncpack lint
         run: pnpm check:deps