Allow to delete some requests

[SebCorbin]

In development, I let silk live in the background and I often spawn its summary page to see page that takes the most time/queries.

Now I sometimes use pdb on some requests so the time calculated for these is not relevant, and it would be nice to have a button to remove them from the DB so that the summary page can be updated.

[LexxLuey]

hello there. i am wondering why the proposed solution by @ashfaq1934 have not been merged?

[ashfaq1934]

Hi @LexxLuey I was hoping to have the pull request that I've created be reviewed by the maintainers before it was merged.

#637