Remove unused workflow.

I'd added this early on with the intent of implementing is but forgot to
come back to it. We should do that at some point.

.github/workflows/lint.yml

@@ -1,23 +0,0 @@
-name: Build
-
-on: [push, pull_request]
-
-jobs:
-  lint:
-    runs-on: windows-latest
-    steps:
-      - name: Check out Git repository
-        uses: actions/checkout@v2
-
-      - name: Set up Node.js
-        uses: actions/setup-node@v1
-        with:
-          node-version: 12
-
-      - name: Install Node.js dependencies
-        run: npm ci
-
-      - name: Lint
-        run: |
-          cd client
-          npm run lint