Add a CI test to verify virtual dynamic shared object (vDSO) functions do not invoke syscalls.

[ivankyluk]

Add a CI test to verify functions covered by vDSO do not invoke syscall and syscall_mix does not count them as syscalls.

Ref: https://man7.org/linux/man-pages/man7/vdso.7.html

C library functions like gettimeofday() and clock_gettime() use the functions in vDSO to bypass system calls.