fix typo in README.md
fix typo in README.md

sjug/perf-tests,shyamjvs/perf-tests,kubernetes/perf-tests,sjug/perf-tests,shyamjvs/perf-tests,kubernetes/perf-tests,shyamjvs/perf-tests,sjug/perf-tests,kubernetes/perf-tests,shyamjvs/perf-tests,kubernetes/perf-tests,shyamjvs/perf-tests,kubernetes/perf-tests,sjug/perf-tests,sjug/perf-tests