fix typo

Author: ianayl

devops/actions/run-tests/benchmark/action.yml

@@ -265,7 +265,7 @@ runs:
           cached_result="$(mktemp -d)/$(basename $results_file)"
           mv "$results_file" "$cached_result"
 
-          git reset --hard "origin/$BENCHMARK_CI_RESULTS"
+          git reset --hard "origin/$BENCHMARK_RESULTS_BRANCH"
           git pull
 
           mv "$cached_result" "$results_file"