Fix blob not found from disk occasionally

[syntrust]

Issue to fix

Check latest blob job in Archive Service Healthcheck workflow failed:

Archive service blobs request failed (HTTP 500)
URL: https://archive.mainnet.ethstorage.io:9645/eth/v1/beacon/blobs/14196131?versioned_hashes=0x01d0cd1c559773411f53c07765405d280b69f325db9b62832bf23b64a8a605d6
Error: Process completed with exit code 

Analysis

According to the fact that a block gets finalized in 64 ~ 95 slots, the adjustment of 64 slots from the latest block to the finalized one is not enough (even with a 32-slot buffer).

To fix it, make it 96 on the safe side.

Tested in this run.