install libxkbcommon-dev for linux build

.github/workflows/ci.yml

@@ -26,6 +26,9 @@ jobs:
     runs-on: ${{ matrix.os }}
 
     steps:
+    - name: Install dependencies
+      run: sudo apt-get install -y libxkbcommon-dev
+      if: matrix.os == 'ubuntu-latest'
     - name: Checkout
       uses: actions/checkout@v2
     - name: Cache build dirs