fix(CI): Install arm64 version of LLVM on arm64 runner

Author: hmelder

.github/workflows/ci.yml

@@ -100,6 +100,11 @@ jobs:
           winget install --accept-source-agreements --accept-package-agreements Ninja-build.Ninja ${{ matrix.arch == 'arm64' && '--architecture arm64' || '' }}
           winget install --accept-source-agreements --accept-package-agreements NASM
 
+      - name: Install LLVM
+        if: contains(matrix.arch, 'arm64')
+        run: |
+          winget install --accept-source-agreements --accept-package-agreements LLVM.LLVM --architecture arm64
+
       - uses: ilammy/msvc-dev-cmd@v1
         with:
           arch: ${{ matrix.arch }}