Change hash of reveal input data to 32 bytes
Currently reveal input requires a Sc_rollup_PVM_sig.Input_hash.t
which has a size of 20 bytes.
There is a consensus that 20 bytes is not cryptographically secure towards collision attacks.
Furthermore, the Tx Kernel host function expects a hash of 32 bytes.
The Reveal
input should be changed to accept a new hash of hash, which has a fixed size of 32 bytes.