Update LLVM install

Author: ehsanmok

.github/workflows/ci.yml

@@ -37,10 +37,9 @@ jobs:
       - uses: actions/checkout@v2
       - name: Install LLVM
         run: |
-          wget -O - https://apt.llvm.org/llvm-snapshot.gpg.key 2>/dev/null | sudo apt-key add -
-          sudo add-apt-repository 'deb http://apt.llvm.org/bionic/ llvm-toolchain-bionic-10 main' -y
-          sudo apt-get update -q
-          sudo apt-get install -y libllvm10 llvm-10 llvm-10-runtime
+          wget https://apt.llvm.org/llvm.sh
+          chmod +x llvm.sh
+          sudo ./llvm.sh 10
 
       - name: Clippy lint
         run: |