installed clang for b2 bootstrapping

Author: joaquintides

.github/workflows/benchmarks.yml

@@ -22,6 +22,7 @@ jobs:
             reportdir: clang-x64
             # os: ubuntu-20.04
             os: [self-hosted, linux, x64]
+            install: clang
             command: sudo cgexec -g memory,cpu:shield sudo -u gha ./benchmark
 
     runs-on: ${{matrix.os}}