Update sudoers.d rules for validator_operators

[MexicanSparker]

Operators may need to run some commands interactively. So far the only two instances found of this scenario are listed below. The sudoers.d rules for validator_operators should allow them to avoid an operator to render useless in a given situation waiting for a sysadmin to come to the rescue.

sudo rm -rf /mnt/snapshots/remote

Only used during a cluster restart to remove all previous snapshots to download new ones.

Additionally when installing apt packages using -y is not allowed

sudo apt install -y

These two are used during cluster restarts

agave-ledger-tool --ledger <ledger-path> create-snapshot
agave-ledger-tool --ledger <ledger-path> latest-optimistic-slots

We could use wildcards in the rule if applicable and convenient.

@eydelrivero @daryl375