feat: Add an OCKAnyOutcome sorting extension

[cbaker6]

Dealing with OCKAnyOutcome's is more complex than the other types. For example, OCKOutcome is versioned, but querying for an OCKOutcome doesn't necessarily follow CareKit's documentation (example1, example2). This seems done on purpose, but may require a developer to query for all OCKOutcome's and filter accordingly. The changes in this PR assists with that by sorting all returned OCKOutcome's with the first item in the array being the greatest for a particular max value.

Some examples are below:

let outcomes = [firstOutcome, secondOutcome]

// Replicates the other OCK versioned types by getting the latest versioned outcome as of today as the first element of the array, the oldest is last.
let sortedOutcomes = outcomes.sortedNewestToOldest(
                \.effectiveDate,
                 lessThanEqualTo: Date()
)

let sortedByCreatedDate = try outcomes.sortedNewestToOldest(
            \.createdDate
)
let sortedByCreatedDate2 = try outcomes.sortedNewestToOldest(
            \.createdDate,
             lessThanEqualTo: secondDate
)
let sortedByOccurrenceIndex = outcomes.sortedNewestToOldest(
            \.taskOccurrenceIndex
)
let sortedByOccurrenceIndex2 = outcomes.sortedNewestToOldest(
            \.taskOccurrenceIndex,
             lessThanEqualTo: firstIndex
)