Replace dummy values with fatal errors in failing implementations

Sources/ElixxirDAppsSDK/Connection.swift

@@ -31,7 +31,7 @@ extension Connection {
 #if DEBUG
 extension Connection {
   public static let failing = Connection(
-    isAuthenticated: { false },
+    isAuthenticated: { fatalError("Not implemented") },
     send: .failing,
     listen: .failing
   )

Sources/ElixxirDAppsSDK/MessageListener.swift

@@ -66,7 +66,7 @@ private class Listener: NSObject, BindingsListenerProtocol {
 #if DEBUG
 extension MessageListener {
   public static let failing = MessageListener { _, _, _ in
-    Data()
+    fatalError("Not implemented")
   }
 }
 #endif

Sources/ElixxirDAppsSDK/NetworkFollowerStatusProvider.swift

@@ -20,7 +20,7 @@ extension NetworkFollowerStatusProvider {
 #if DEBUG
 extension NetworkFollowerStatusProvider {
   public static let failing = NetworkFollowerStatusProvider {
-    .unknown(code: -1)
+    fatalError("Not implemented")
   }
 }
 #endif

Sources/ElixxirDAppsSDK/NetworkWaiter.swift

@@ -19,7 +19,7 @@ extension NetworkWaiter {
 #if DEBUG
 extension NetworkWaiter {
   public static let failing = NetworkWaiter { _ in
-    false
+    fatalError("Not implemented")
   }
 }
 #endif

Sources/ElixxirDAppsSDK/PasswordGenerator.swift

@@ -20,7 +20,7 @@ extension PasswordGenerator {
 #if DEBUG
 extension PasswordGenerator {
   public static let failing = PasswordGenerator { _ in
-    Data()
+    fatalError("Not implemented")
   }
 }
 #endif