SpeechAdaptation constructor
      
      SpeechAdaptation({ 
    
    
- ABNFGrammar? abnfGrammar,
- List<CustomClass> ? customClasses,
- List<String> ? phraseSetReferences,
- List<PhraseSet> ? phraseSets,
Implementation
SpeechAdaptation({
  this.abnfGrammar,
  this.customClasses,
  this.phraseSetReferences,
  this.phraseSets,
});