Deletes the specified pronunciation lexicon stored in an AWS Region. A lexicon which has been deleted is not available for speech synthesis, nor is it possible to retrieve it using either the GetLexicon or ListLexicon APIs.
/// Amazon Polly can't find the specified lexicon. This could be caused by a lexicon that
/// is missing, its name is misspelled or specifying a lexicon that is in a different
/// region.
///
///
///
/// Verify that the lexicon exists, is in the region (see ListLexicons) and that
/// you spelled its name is spelled correctly. Then try again.
///
///
/// An unknown condition has caused a service failure.
///