fix acala email contribution

Author: PankraSerg

feature-crowdloan-impl/src/main/java/jp/co/soramitsu/feature_crowdloan_impl/domain/contribute/custom/acala/AcalaContributeInteractor.kt

@@ -45,14 +45,18 @@ class AcalaContributeInteractor(
             val selectedAccount = accountRepository.getSelectedAccount()
             val statementSignature = accountRepository.signWithAccount(selectedAccount, statement.toByteArray())
 
+            val useEmail = when  {
+                payload.email.isNullOrEmpty() -> null
+                else -> payload.email
+            }
             acalaApi.contribute(
                 apiUrl, "Bearer $apiKey",
                 AcalaContributeRequest(
                     address = selectedAccount.address,
                     amount = Token.Type.DOT.planksFromAmount(amount),
                     signature = statementSignature.toHexString(true),
                     referral = payload.referralCode,
-                    email = payload.email,
+                    email = useEmail,
                     receiveEmail = payload.agreeReceiveEmail
                 )
             )
@@ -63,13 +67,17 @@ class AcalaContributeInteractor(
     private suspend fun performTransfer(payload: AcalaBonusPayload, amount: BigDecimal, apiUrl: String, apiKey: String): Result<Unit> = runCatching {
         httpExceptionHandler.wrap {
             val address = accountRepository.getSelectedAccount().address
+            val useEmail = when  {
+                payload.email.isNullOrEmpty() -> null
+                else -> payload.email
+            }
             acalaApi.transfer(
                 apiUrl, "Bearer $apiKey",
                 AcalaTransferRequest(
                     address = address,
                     amount = Token.Type.DOT.planksFromAmount(amount),
                     referral = payload.referralCode,
-                    email = payload.email,
+                    email = useEmail,
                     receiveEmail = payload.agreeReceiveEmail
                 )
             )