CI: Add webclient (#4478)

.github/workflows/desktop-lint.yml

@@ -0,0 +1,30 @@
+name: Code Style (C++) 
+
+on:
+  pull_request:
+    branches:
+    - master
+    paths-ignore:
+      - '**.md'
+      - 'webclient/**'
+      - '.github/workflows/web-*.yml'
+
+jobs:
+  clang-format:
+    runs-on: ubuntu-latest
+
+    steps:
+    - name: Checkout
+      uses: actions/checkout@v2
+      with:
+        fetch-depth: 20 # should be enough to find merge base
+
+    - name: Install clang-format
+      shell: bash
+      run: |
+        sudo apt-get update
+        sudo apt-get install -y --no-install-recommends clang-format
+
+    - name: Run clangify
+      shell: bash
+      run: ./.ci/lint_cpp.sh