Trigger first validation before waiting for interval

[rytswd]

WHAT

Update the validation triggering logic to trigger the first validation without waiting for the interval

WHY

Some CI jobs are quick to complete, and because Docker image creation usually takes about 30sec, it's good to get started with the first validation as soon as the Docker container is ready. This reduces the unnecessary wait, and should only cause minor behaviour change for repository with longer running jobs.

[hlts2]

thank you for PR :bow: I reviewed it and It looks good to me! :+1:

btw, It seems that there are others like us who would like to have an immediate tic. https://stackoverflow.com/questions/32705582/how-to-get-time-tick-to-tick-immediately

And I tried to publish it as a library to make others useful. When I offered it as a library, I found other approaches easier to implement, so I implemented them in a different way. :+1: https://github.com/hlts2/gticker

[rytswd]

https://github.com/hlts2/gticker

Nice addition! 👍 As this project only has this single use case, it's probably an overkill to introduce another dependency just for that, but we can certainly look to use it if we find more cases!