Don't display the default data directory in --help output because if it is too long, it causes Picocli to enter an infinite loop. (#148)

pantheon/src/main/java/tech/pegasys/pantheon/cli/PantheonCommand.java

@@ -142,7 +142,7 @@ public class PantheonCommand implements Runnable {
   @Option(
     names = {"--datadir"},
     paramLabel = MANDATORY_PATH_FORMAT_HELP,
-    description = "the path to Pantheon data directory (default: ${DEFAULT-VALUE})"
+    description = "the path to Pantheon data directory"
   )
   private final Path dataDir = getDefaultPantheonDataDir();
 

pantheon/src/test/java/tech/pegasys/pantheon/cli/PantheonCommandTest.java

@@ -60,7 +60,6 @@ import org.junit.rules.TemporaryFolder;
 import org.mockito.ArgumentCaptor;
 import org.mockito.ArgumentMatchers;
 
-@Ignore("temporarily ignored because tests hang if working dir path too long")
 public class PantheonCommandTest extends CommandTestAbstract {
 
   @Rule public final TemporaryFolder temp = new TemporaryFolder();