JobMetadata constructor
      
      JobMetadata({ 
    
    
- List<BigTableIODetails> ? bigTableDetails,
- List<BigQueryIODetails> ? bigqueryDetails,
- List<DatastoreIODetails> ? datastoreDetails,
- List<FileIODetails> ? fileDetails,
- List<PubSubIODetails> ? pubsubDetails,
- SdkVersion? sdkVersion,
- List<SpannerIODetails> ? spannerDetails,
- Map<String, String> ? userDisplayProperties,
Implementation
JobMetadata({
  this.bigTableDetails,
  this.bigqueryDetails,
  this.datastoreDetails,
  this.fileDetails,
  this.pubsubDetails,
  this.sdkVersion,
  this.spannerDetails,
  this.userDisplayProperties,
});