Remove DefaultTimeConverterIsIdentity test

[ddelgadovargas-cyber]

The DefaultTimeConverterIsIdentity test in ApproximateClockTest.cpp was failing because it relies on the state of a global static variable returned by get_time_converter(). If other tests in the same binary run first and modify this state, the test fails because the converter is no longer the identity function.

third_party/libkineto/test/ApproximateClockTest.cpp:105: Failure
Expected equality of these values:
  converter(kTestValue)
    Which is: 0
  static_cast<libkineto::time_t>(kTestValue)
    Which is: 123456789
Stack trace:
0x7fb663e19a5a: ApproximateClockTest_DefaultTimeConverterIsIdentity_Test::TestBody() @ ??:??
0x7fb5f80e4086: testing::Test::Run() @ ??:??
0x7fb5f80e50db: testing::TestInfo::Run() @ ??:??
... Google Test internal frames ...

This test validates the identity function in its initial state, which is not very useful. This change removes the test case.

[scotts]

Digging into this, I think we should just remove this test entirely. get_time_converter() being the identity function is its initial state that we expect to be modified in:

kineto/libkineto/src/GenericActivityProfiler.cpp

Line 477 in ea8bc18

get_time_converter() = clockConverter.makeConverter();

This test, then, is not actually testing anything useful.

[ddelgadovargas-cyber]

@scotts , I updated the PR header and removed the test case.

[meta-codesync]

@scotts has imported this pull request. If you are a Meta employee, you can view this in D105224372.

[meta-codesync]

@scotts merged this pull request in 81d31cd.