Zig test - run single-thread (only)

[kassane]

Run the fibonacci sample C in comparison to Zig test . A discrepancy in runtime between the zig test and fib-c is perceived.

Note: This comparison occurs if you put the same values into the fib(n) function. The zig test has smaller numbers to better pass the CI test.

Reference

• Consider running tests in parallel by deafult ziglang/zig#15953

[kassane]

Although zig test run sequentially, it only displays the output after finishing all calculations. Different from the sample application.