Unnecessary cloning in perform_annotated_read_operation

[jdm]

let blobtype = read_data.blobtype.clone();
let label = read_data.label.clone();

There's no need for this cloning, since we're just moving the values immediately. I think we can just remove the variables entirely and use readdata.whatever when necessary.

Code: components/script/dom/filereader.rs

[farodin91]

By closing the issue #6768, i think, this also closed.

[farodin91]

Will do this.