[Image Resizer]: Option to force Fallback encoder

Description of the new feature / enhancement

Add an option to the Image Resizer tool to always apply the Fallback encoder, regardless if the encoder of the original format is available, so the tool can resize and re-encode images on a different format in a single step.

Scenario when this would be used?

With the option enabled a user can select a bunch of PNG images on the File Explorer and resize and re-encode them in JPG all in one go. Useful when dealing with several images on various formats that should be optimized, in both format and size, for deployment e.g. web.

Supporting information

No response