Are you using an HP Laptop?
How did you get on with this issue as I have just started getting the same prompt?
It seems that a few people have also asked this on HPs website and my investigation of the file found it to be located in AppData\Local\Temp*HPDIAGS*\64819556-07a0-42c4-a925-bba17af6db61
This seems to suggest it is an HP diagnostic tool of some kind. Also the properties of the file indicate that it is digitally signed by HP Inc.
In the same folder is are 2 other files; a CSV (spreadsheet file) and a text file. Both files indicate that it has something to do with the Laptops NVMe hard drive - on my PC it lists the modal number as KXG50ZNV1T02 TOSHIBA.
So my guess is that the DST exe file is some monitoring tool for the laptops hard drive and probably perfectly safe.
It might be worth confirming that with HP.