AzureFileCopy produces application/octet-stream files in blob

Question

I am using the AzureFileCopy task to copy files to a blob for a cdn, but all my new files end up as application/octet-stream by default. Is there any way this can be changed?

steps:
- task: AzureFileCopy@1
  displayName: ' File Copy - blob'
  inputs:
    SourcePath: '$(System.DefaultWorkingDirectory)/xxxxxx/blob'
    azureSubscription: 'xxxxxx'
    Destination: AzureBlob
    storage: xxxxxx
    ContainerName: cdn