public static String getPluginPath() {
    String pluginDir = System.getenv(AMORO_PLUGIN_DIR);
    if (pluginDir != null) {
      return pluginDir;
    }
    return getHomePath() + "/" + DEFAULT_PLUGIN_DIR_NAME;
  }
Get the path of plugins which is a directory contains jars of plugins.

@return The plugin path.
amoro-ams/src/main/java/org/apache/amoro/server/Environments.java