abstract fun <T> newCollectingAssertionContainer(maybeSubject: Option<T>): CollectingAssertionContainer<T>Creates a CollectingAssertionContainer which is intended to be used as receiver object in lambdas so that it can collect Assertions created inside the lambda.
maybeSubject - Either Some wrapping the subject of the current assertion or
None in case a previous subject change was not successful.
Return
The newly created assertion container.