Limit the max number of iterations we perform in ProtoLog perf tests

Spamming protolog messages in a loop leads to a build up of lambdas in the thread pool queue which at some point leads to an OOM in the test. This address this issue by giving limit that amount of logging lambdas we push to the thread pool.

Bug: 361740975
Test: atest ProtoLogPerfTests
Flag: TEST_ONLY
Change-Id: I60636625ab82965337cdb81d0df7c122db08ad76