Add regression test for fixed crasher

Author: slavapestov

validation-test/compiler_crashers_2_fixed/0195-sr10438.swift

@@ -0,0 +1,20 @@
+// RUN: %target-swift-frontend -typecheck %s
+
+protocol AuthenticationFlowStateMachine {
+    associatedtype StartState: AuthenticationFlowStateMachineStartState where StartState.StateMachine == Self
+    associatedtype NonFinalState: AuthenticationFlowStateMachineNonFinalState where NonFinalState.StateMachine == Self
+    associatedtype FlowError: AuthenticationFlowStateMachineFlowError where FlowError.StateMachine == Self
+}
+
+protocol AuthenticationFlowStateMachineFlowError: Error {
+    associatedtype StateMachine: AuthenticationFlowStateMachine where StateMachine.FlowError == Self
+}
+
+protocol AuthenticationFlowStateMachineStartState {
+    associatedtype StateMachine: AuthenticationFlowStateMachine where StateMachine.StartState == Self
+    var nonFinalState: StateMachine.NonFinalState { get }
+}
+
+protocol AuthenticationFlowStateMachineNonFinalState {
+    associatedtype StateMachine: AuthenticationFlowStateMachine where StateMachine.NonFinalState == Self
+}