I think, we probably shouldn't implement RemoveCredential()

[chiro-hiro]

Regarding this section https://www.w3.org/TR/did-core/#persistence.

DIDs are designed to be persistent such that a controller need not rely upon a single trusted third party or administrator to maintain their identifiers. In an ideal case, no administrator can take control away from the controller, nor can an administrator prevent their identifiers' use for any particular purpose such as authentication, authorization, and attestation. No third party can act on behalf of a controller to remove or render inoperable an entity's identifier without the controller's consent.

So, I think the revoke process should be tracked.

https://github.com/whalelephant/CertX/blob/main/certX/x/credentials/keeper/credential.go#L88

// RemoveCredential removes a credential from the store
func (k Keeper) RemoveCredential(ctx sdk.Context, id uint64) {
	store := prefix.NewStore(ctx.KVStore(k.storeKey), types.KeyPrefix(types.CredentialKey))
	store.Delete(GetCredentialIDBytes(id))
}