7 files declare their use of RecurringKernelTestBase in Commerce Recurring Framework 8

PaymentDeclinedMailTest.php in tests/src/Kernel/Mail/PaymentDeclinedMailTest.php

ProductVariationTest.php in tests/src/Kernel/Plugin/Commerce/SubscriptionType/ProductVariationTest.php

ProportionalTest.php in tests/src/Kernel/Plugin/Commerce/Prorater/ProportionalTest.php

RetryTest.php in tests/src/Kernel/Plugin/AdvancedQueue/JobType/RetryTest.php

StandaloneTest.php in tests/src/Kernel/Plugin/Commerce/SubscriptionType/StandaloneTest.php

SubscriptionActivateTest.php in tests/src/Kernel/Plugin/AdvancedQueue/JobType/SubscriptionActivateTest.php

SubscriptionTest.php in tests/src/Kernel/Entity/SubscriptionTest.php