Fix ThreadStateSamplerTest flicker

[jasonjkeller]

Hmm ThreadStateSamplerTest seems to flicker pretty badly. The test passes locally but seems to fail consistently when run on PRs. I’ve seen numerous failures on a PR that doesn’t even touch agent functionality.

com.newrelic.agent.threads.ThreadStateSamplerTest > testCpuTimeMetrics FAILED
    java.lang.AssertionError at ThreadStateSamplerTest.java:57

The assertion looks to be:

        assertTrue("TotalTime: " + totalTimeSeconds + ", SystemTime: " + systemTimeSeconds + ", UserTime: " + userTimeSeconds,
                totalTimeSeconds + 0.2 >= systemTimeSeconds + userTimeSeconds); // account for rounding error