CRM_Core_Resources - Use splats, CollectionAdderTrait, CollectionAdderInterface

CRM_Core_Resources - Use splats, CollectionAdderTrait, CollectionAdderInterface

Before
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`CRM_Core_Resources` directly implements a number of functions (`addFoo()`)

After
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`CRM_Core_Resources` re-uses the implementations from `CollectionAdderTrait`

Comment
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The method signatures in `CollectionAdderTrait` look different, but they are
compatible.  In particular, the use of splat (`...$options`) means that they
can accept either key-value options or positional options. The existing
test-cases in `CollectionTestTrait` assert as much.