Fix epochs that have extra blocks

[linuskendall]

For some epochs the 'last block detection' didn't work, which the PoH validation showed. We need to regenerate these epochs and re-upload them with the corrected last epoch.

[linuskendall]

@gagliardetto to add some details on how we will do this with radiance so that it knows where to stop (pick a fork from the correct snapshot).

[gagliardetto]

In https://github.com/gagliardetto/radiance-triton I added a --stop-at-slot=999999999 flag (inclusive) that cuts the excess blocks from epochs that have them (you need to know the slot you need).