Save test metrics to openmetrics

[dvalinrh]

Description

1. Adds code to save the test metrics to pcp openmetrics.
2. Add timestamps
3. Convert colon in csv file to be ,

Before/After Comparison

Before: Test metrics only saved in csv file
After: Test metrics save in both csv file and pcp openmentrics.

Clerical Stuff

This closes #30

Relates to JIRA: RPOPC-774

Test results

command executed:
/home/ec2-user/workloads/linpack-wrapper/linpack/linpack_run --run_user ec2-user --home_parent /home --iterations 1 --tuned_setting tuned_none_sys_file_ --host_config "m7i.xlarge" --sysname "m7i.xlarge" --sys_type aws --use_pcp

csv file
ht_config,sockets,threads,unit,MB/sec,cpu_affin,Start_time,End_time,Start_Date,End_Date
ht_yes_1_socket,1,2,GFlops,182,0.1,2026-01-28T20:18:02Z,2026-01-28T20:18:39Z
ht_yes_1_socket,1,2,GFlops,175,2.3.0.1,2026-01-28T20:18:02Z,2026-01-28T20:18:39Z

====================================
pcp snippet

      o.w.iteration  o.w.running  o.w.numthreads  o.w.runtime  o.w.throughput  o.w.latency  o.w.hyper_thread  o.w.num_sockets  o.w.gflops

14:37:08 1.000 1.000 2.000 NaN NaN NaN 1.000 1.000 132.000
14:37:09 1.000 1.000 2.000 NaN NaN NaN 1.000 1.000 132.000
14:37:10 1.000 1.000 2.000 NaN NaN NaN 1.000 1.000 132.000

-x output
linpack_x.txt

================================================================================

[github-actions]

This relates to RPOPC-774

[frival]

Benchmark names have meaning. ;)

[frival]

LGTM