When we look for matching annotations in TestBed, we should always take the last
matching annotation. Otherwise, we will return superclass data for subclasses,
which would have unintended consequences like directives matching the wrong selectors.
PR Close#28195
In some cases in our tests we can define multiple overrides for a given class. As a result, only the last override is actually applied due to the fact that we store overrides in a Type<->Override map. This update changes the logic to keep all overrides defined in a given test for a Type (i.e. Type<->Override[] map) and applies them one by one at resolution phase. This behavior is more inline with the previous TestBed.
PR Close#27734
