[Php] Exclude query params when they're not required

Created by: ksvirkou-hubspot

Exclude query params when they're not required

{
    "name": "archived",
    "in": "query",
    "description": "Whether to return only results that have been archived.",
    "required": false,
    "style": "form",
    "explode": true,
    "schema": {
        "type": "boolean",
        "default": false
    }
}

if archived is empty https://api.*.com/crm/v3/objects/contacts

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