Lookup methods can support arguments, find a target bean based on the return type, and be identified by an @Lookup annotation

Issue: SPR-7431
Issue: SPR-5192
Polishing
Fixed fragile tests for @Bean method overloading
Polishing
Support merging custom TELs with default TELs

Prior to this commit, if a custom TestExecutionListener was registered
via @TestExecutionListeners the defaults would not be registered. Thus,
if a user wanted to declare a custom listener and use the default
listeners, the user was forced to manually declare all default
listeners in addition to any custom listeners. This unfortunately
required that the user know exactly which listeners were registered by
default. Moreover, the set of default listeners can change from release
to release, and with the support for automatic discovery of default
listeners introduced in SPR-11466 it is no longer even possible to know
what the set of default TestExecutionListeners is before runtime.

This commit addresses this issue by introducing a mechanism for merging
custom declared listeners with the defaults for the current
environment. Specifically, @TestExecutionListeners supports a new
MergeMode that is used to control whether or not explicitly declared
listeners are merged with the default listeners when
@TestExecutionListeners is declared on a class that does not inherit
listeners from a superclass.

Issue: SPR-8854