Rework batch processor to elaborate in code comments / avoid while(...) loops

There's a code in Batch Log processor that contains the following constructs:

  while (is_force_flush_.load() == true)
  {
    cv_.notify_one();
  }

These constructs look suspicious, as "what if" the other thread does not refresh the is_force_flush value - does it mean that we are effectively busy-waiting, burning CPU cycles?

Should this be supplemented with some timed idle-wait or with std:🧵:yield , or reworked using conditional variables?

Discussed with @open-telemetry/cpp-approvers during SIG call that the code as it is coded - looks funky, but should be fine .. Let's see if it can be reworked long-term to look cleaner.

Start by locating the Batch Log processor and the while loop checking is_force_flush_.load(), then review the surrounding condition-variable and notification logic. Compare the current behavior with the issue's proposed timed wait, yield, or conditional-variable approaches; done means a cleaner design that avoids unnecessary busy-waiting without changing force-flush behavior.