[memprof][test] Make test_terse.cpp robust (sched_getcpu may happens to change)

```
/b/sanitizer-x86_64-linux/build/llvm-project/compiler-rt/test/memprof/TestCases/test_terse.cpp:11:11: error: CHECK: expected string not found in input
// CHECK: MIB:[[STACKID:[0-9]+]]/1/40.00/40/40/20.00/20/20/[[AVELIFETIME:[0-9]+]].00/[[AVELIFETIME]]/[[AVELIFETIME]]/0/0/0/0
          ^
<stdin>:1:1: note: scanning from here
MIB:StackID/AllocCount/AveSize/MinSize/MaxSize/AveAccessCount/MinAccessCount/MaxAccessCount/AveLifetime/MinLifetime/MaxLifetime/NumMigratedCpu/NumLifetimeOverlaps/NumSameAllocCpu/NumSameDeallocCpu
^
<stdin>:4:1: note: possible intended match here
MIB:134217729/1/40.00/40/40/20.00/20/20/7.00/7/7/1/0/0/0
```