Fails to uploads HTML to AEM DAM

### Expected Behaviour
The AEMUpload class should allow to upload HTML files to DAM

### Actual Behaviour
HTML files fail to upload because AEM tries to validate them as JSON files. Seeing the error:

`Upload START 'index.html': 319901 bytes
Upload FAILED 'index.html': 'Unexpected token < in JSON at position 0 while parsing near '

Start in the AEMUpload class and trace the upload path used by @adobe/aem-upload, focusing on where the file MIME type is ignored and HTML is treated as JSON. Reproduce with an HTML file such as index.html; done means the upload reaches AEM DAM without the JSON parsing error.

Written by the indexing model from the issue text.