FTS: Wrong sort order when mixing SearchSort and String

Suggested Release Note:

Fixed a regression in Java SDK 3.4.5 that could cause Full-Text Search results to be sorted in the wrong order if the sort option was specified using a mix of strings and `SearchSort` objects.

Example:

cluster.searchQuery(

  "myIndex",

  SearchQuery.queryString("pool"),

  SearchOptions.searchOptions()

    .sort("type", SearchSort.byField("description"))

);

Set a breakpoint in ClassicCoreSearchOps.injectOptions where the sort array is generated.

expected value for the sort field:

["type",{"by":"field","desc":false,"field":"name"}]

actual value:

[{"by":"field","desc":false,"field":"name"},"type"]

Note that the sort tiers specified as strings are always appended to the end of the list, instead of appearing in the order they were added to the sort.