Stronger lambda error (#4771)

* Make sure lambdaError() make the test fail in all circumstances.

* Fix existing errors on tests.

* Uniformize the way we are creating class under test.

* Cleanup

* Fix typo

* Fix failing test after rebase.

tests/testutils/src/main/kotlin/io/element/android/tests/testutils/lambda/Error.kt

@@ -7,8 +7,19 @@
 
 package io.element.android.tests.testutils.lambda
 
+import kotlin.system.exitProcess
+
 fun lambdaError(
     message: String = "This lambda should never be called."
 ): Nothing {
-    throw AssertionError(message)
+    // Throwing an exception here is not enough, it can be caught.
+    // Instead exit the process to make sure the test fails.
+    // The error will be:
+    // "Could not stop all services."
+    // In this case, put a breakpoint here and run the test in debug mode to identify which lambda is failing.
+    System.err.println(message)
+    Thread.currentThread().stackTrace.forEach {
+        System.err.println(it)
+    }
+    exitProcess(1)
 }