Update ci.yml

Author: ramsafin

.github/workflows/ci.yml

@@ -37,7 +37,7 @@ jobs:
       - name: Set up ${{ matrix.compiler }}
         run: |
           sudo apt update
-          sudo apt update && sudo apt install -y cmake ninja-build g++ gcc
+          sudo apt update && sudo apt install -y cmake ninja-build g++ gcc clang
           if [ "${{ matrix.compiler }}" = "clang" ]; then
             sudo apt install -y clang lld
             echo "CC=clang" >> $GITHUB_ENV