Retrieve link from `items/{item_id}` contains wrong parameters

[dalpasso]

To reproduce, first search a product:

POST http://127.0.0.1:8000/search

{
    "collections": ["AG_ERA5"],
    "query": {
        "federation:backends": {"eq": "cop_cds"},
        "day": {"eq": "02"},
        "month": {"eq": "03"},
        "time": {"eq": "06_00"},
        "variable": {"eq": "2m_relative_humidity"},
        "version": {"eq": "1_1"},
        "year": {"eq": "1981"}
    }
}

The response contains a self link:

{
	"rel": "self",
	"type": "application/geo+json",
	"href": "http://127.0.0.1:8000/collections/AG_ERA5/items/AG_ERA5_ORDERABLE_6436ec40cef0d146debef37ecb0d6a8728e47284",
	"title": "Original item link"
}

Get the self link. The retrieve link of the response contains only some parameters. Some of them are not the ones from the initial search or are not queryables:

{
	"rel": "retrieve",
	"type": "application/geo+json",
	"href": "http://127.0.0.1:8000/collections/AG_ERA5/order",
	"method": "POST",
	"title": "Retrieve",
	"body": {
		"year": [
			"1979"
		],
		"month": [
			"01"
		],
		"day": [
			"01"
		],
		"dataset_id": "EO:ECMWF:DAT:SIS_AGROMETEOROLOGICAL_INDICATORS",
		"itemsPerPage": 200,
		"startIndex": 0
	}
},