Add parameters for sorting options (GSI-329)

[TheByronHimes]

Main change: Adds a way to control how the results are sorted, via the sorting_parameters parameter (a list of objects, each with "field" and "order")
e.g.

{
  "class_name": "Dataset",
  "query": "",
  "filters": [],
  "skip": 0,
  "limit": 0,
  "sorting_parameters": [
    {
      "field": "title",
      "order": "descending"
    },
    {
      "field": "id_",
      "order": "ascending"
    }
  ]
}

Some notes:

• Duplicate field names will result in a validation error from pydantic. This is because the parameters for the sort operation in mongo are a single dictionary.
• If id_ is not passed in explicitly, it will be added as the final sort key by the QueryHandler, and always in ascending order.
• The facets section of the aggregation pipeline now runs unconditionally, and the sorting takes place therein right after the renaming of the ID field. Previously there was a condition to only run the function when there were facetable properties supplied. The config conditions mean that, in practice, it will always run.

[github-actions]

Pull Request Test Coverage Report for Build 6074312337

• 28 of 28 (100.0%) changed or added relevant lines in 5 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.5%) to 90.766%

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Totals
Change from base Build 6037320504:	0.5%
Covered Lines:	403
Relevant Lines:	444

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