* std::chrono does not provide enough granularity for microsecs and periodically emits
duplicates
* the bug is manifested in log rotation logic where we get duplicate
log file names and loose previous log content
* msvc does not imlement COW on std::strings adjusted the test to use
refs in the loops as auto does not retain ref info
* adjust auto_log rotation test with Windows specific command to remove
a folder. The test previously worked because we have unix utils installed
in house but this may not be the case for everyone.
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