// MasterPodName gets the master pod name of the Alluxio cluster by parsing the output of `alluxio   fsadmin report`.
// This function is primarily responsible for executing the report command in the Alluxio container
// and extracting the master address from the parsed output results.
//
// Returns:
//   - masterPodName (string): The extracted master pod name or address. Returns the current pod name on failure.
//   - err (error): Returns an error if the command execution fails or the output format is invalid.