Don't throw when canceling prompt

[qudix]

Just a minor visual annoyance, I tend to cancel running prompts midway rather often and it results in the console getting filled with tracebacks due to this seemingly? unnecessary exception (on user action at least). I feel this could be made to simply log a one line processing interrupted message instead, or just nothing at all.

[comfyanonymous]

Should be fixed with: 02ca1c6