GODT-1986: Handle case where an address has no decryption entities

It's possible (but very rare, I don't think proton still allows it)
for an address to have no keys. If we try to load the address keyring
for such an address, this change logs a warning that no decryption
entities were found in the unlocked keyring.

It bumps liteapi to a version that does not return an error when no
keys could be unlocked.

tests/api_test.go

@@ -33,6 +33,8 @@ type API interface {
 
 	CreateAddress(userID, address string, password []byte) (string, error)
 	RemoveAddress(userID, addrID string) error
+	GetAddressKeyIDs(userID, addrID string) ([]string, error)
+	RemoveAddressKey(userID, addrID, keyID string) error
 
 	Close()
 }