sendFileContentsAsObservable uploads file contents to the server for a specific resource. The file is uploaded
via FormData with the appropriate scope and public flag settings.
Parameters
resourceKey: string
The key of the resource to upload file contents for
fileToUpload: File|Blob
The file or blob to upload
publicFlag: boolean
Whether the file should be public
Returns Observable<boolean>
Observable resolving to true if upload was successful
sendFileContentsAsObservable uploads file contents to the server for a specific resource. The file is uploaded via FormData with the appropriate scope and public flag settings.