Fix: Issue 10520 - [profile+nothrow] Building with profiler results in "is not nothrow" error on some contracts

When Statement#blockExit() checks if the statements may throw or not, it
can also emit compile error.
We turn the second argument of it, mustNotThrow, to false
so that the error is suppressed.
Merge pull request #3554 from qchikara/FIX_profile_contract_nothrow

Fix: Issue 10520 - [profile+nothrow] Building with profiler results in "...