private Program getGzfProgram(String gzfProgName) throws IOException {
		// It is assumed that program has been added to TestEnv short-term cache before this method
		// is invoked, if not resourcesTestDataDir will be checked for gzfProgName
		return getGzfProgram(resourcesTestDataDir, gzfProgName);
	}
Get the loader class which should be used.  A null value should be
return to use the preferred loader.
@return loader class or null
Ghidra/Features/Base/src/main/java/ghidra/test/processors/support/ProcessorEmulatorTestAdapter.java