add 24 test cases covering all benchmark functionality:
- Benchmark.measure and Benchmark.realtime
- Benchmark::Tms class and its methods (total, to_s, format)
- Benchmark.bm for formatted comparison reports
- Benchmark::Report class
- memory tracking with ObjectSpace integration
- consistency and realistic usage scenarios
suppress output during tests by temporarily setting $stdout to nil
for tests that call Benchmark.bm or Report#report to avoid printing
garbage during test execution.
all tests pass successfully.
Co-authored-by: Claude <noreply@anthropic.com>
Yukihiro "Matz" Matsumoto