Zero: Drop incorrect test block from compiler/startup/NumCompilerThreadsCheck.java

There is a Zero-specific test block in compiler/startup/NumCompilerThreadsCheck.java, which currently fails:

$ CONF=linux-x86_64-zero-fastdebug make exploded-test TEST=compiler/startup/NumCompilerThreadsCheck.java
...

STDERR:
 stdout: [];
 stderr: [intx CICompilerCount=-1 is outside the allowed range [ 0 ... 2147483647 ]
Improperly specified VM option 'CICompilerCount=-1'
Error: Could not create the Java Virtual Machine.
Error: A fatal exception has occurred. Program will exit.
]
 exitValue = 1

java.lang.RuntimeException: 'must be at least 0' missing from stdout/stderr

at jdk.test.lib.process.OutputAnalyzer.shouldContain(OutputAnalyzer.java:221)
at compiler.startup.NumCompilerThreadsCheck.main(NumCompilerThreadsCheck.java:53)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:77)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:568)
at com.sun.javatest.regtest.agent.MainActionHelper$AgentVMRunnable.run(MainActionHelper.java:312)
at java.base/java.lang.Thread.run(Thread.java:833)

I believe it was rendered obsolete by JDK-8122937.