Exolix integration: bugfix apiToken on fetchRates (#1120)

* Add Exolix exchange integration

* update tx payload

* remove import

* Improve mapping

* Additional fixes

* fix apiBaseUrl

* Update trade_details_view_model.dart

* Update exolix_exchange_provider.dart

* Fix status URL

* Fix fetch rates API error handling update limits API to use a valid amount and validate on success status code

* bugfix added apiToken for fetchRate

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Co-authored-by: Justin Ehrenhofer <justin.ehrenhofer@gmail.com>
Co-authored-by: Omar Hatem <omarh.ismail1@gmail.com>

tool/utils/secret_key.dart

@@ -32,6 +32,7 @@ class SecretKey {
     SecretKey('fiatApiKey', () => ''),
     SecretKey('payfuraApiKey', () => ''),
     SecretKey('chatwootWebsiteToken', () => ''),
+    SecretKey('exolixApiKey', () => ''),
     SecretKey('robinhoodApplicationId', () => ''),
     SecretKey('robinhoodCIdApiSecret', () => ''),
     SecretKey('walletConnectProjectId', () => ''),