[DO NOT MERGE] Test code

Author: tillh-stripe

payments-core/src/main/java/com/stripe/android/model/CreateFinancialConnectionsSessionParams.kt

@@ -52,7 +52,9 @@ sealed interface CreateFinancialConnectionsSessionParams {
                 PARAM_CLIENT_SECRET to clientSecret,
                 PARAM_HOSTED_SURFACE to hostedSurface,
                 PARAM_LINK_MODE to linkMode.valueForHostedSurface(hostedSurface),
-                PARAM_PAYMENT_METHOD_DATA to paymentMethod.toParamMap()
+                PARAM_PAYMENT_METHOD_DATA to paymentMethod.toParamMap(),
+                // TODO: Remove testing code
+                "initial_institution" to "bcinst_Jg18xEfPHevfHP",
             ).filterNotNullValues()
         }
     }

payments-core/src/main/java/com/stripe/android/payments/bankaccount/CollectBankAccountLauncher.kt

@@ -81,7 +81,8 @@ interface CollectBankAccountLauncher {
         ): CollectBankAccountLauncher {
             return CollectBankAccountForACHLauncher(
                 // L1 (public standalone) integration is not hosted by any Stripe surface.
-                hostedSurface = null,
+                // TODO: Reset this to null before merging
+                hostedSurface = "payment_element",
                 hostActivityLauncher = activity.registerForActivityResult(CollectBankAccountContract()) {
                     callback(it.toUSBankAccountResult())
                 }