add compile time flags in prints

[briancoutinho]

Related to an issue we saw on FAIR research cluster, some of the compille time flags were not set as expected.
This change prints them so we can easily debug issues.
Meta task - https://www.internalfb.com/T156657507

TestPlan:
Ran on test docker container.

root@e29f5504c399:/workspace/dynolog# ./build/bin/dynolog --use_scuba --scribe_category test --kernel_monitor_reporting_interval_s 10 --use_JSON --use_ODS
I20230823 22:40:52.596849 28682 Main.cpp:147] Starting dynolog, version = 0.3.0, build git-hash = 75af067
I20230823 22:40:52.600204 28682 Main.cpp:149] Build Config:
I20230823 22:40:52.600279 28682 Main.cpp:150]   USE_GRAPH_ENDPOINT = 1
I20230823 22:40:52.600323 28682 Main.cpp:157]   USE_JSON_GENERATED_PERF_EVENTS = 0
I20230823 22:40:52.600371 28682 Main.cpp:163]   USE_PROMETHEUS = 0

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