Feat: Update AccountsClose to be safe to call manually

[stegaBOB]

Updates the AccountsClose trait to ensure its safe to call manually.

Also removed the warnings and added more tests to make sure its safe. Also added AccountsClose to the prelude.

[vercel]

@stegaBOB is attempting to deploy a commit to the coral-xyz Team on Vercel.

A member of the Team first needs to authorize it.

[Henry-E]

@armaniferrante The core part of this change is switching
if &T::owner() == program_id {
to
if self.info.owner == program_id {
If that's a safe change to make then we should totally do this. But I don't feel qualified yet to comment on using the owner trait vs. the self.info.owner value.

[stegaBOB]

This may actually cause issues if assign is called manually. I'm not sure if the serialization would normally fail in that case. I'm going to do an additional test here first and I'll report back.

[stegaBOB]

@Henry-E @armaniferrante I updated the AccountsExit logic and it should prevent any false positives from being triggered on accounts with reassigned owners.

[stegaBOB]

This PR should be ready to merge in. The failed workflow runs fails were GitHub network errors.