Description of problem:
Wrong _href in the response body of consumer profile creation

$ curl -H "Accept: application/json" -X POST -k -u admin:admin -d '{"content_type": "rpm","profile": [{"arch": "i686","epoch": 0,"name": "glib2","release": "2.fc17","vendor": "Fedora Project","version": "2.32.4"},{"arch": "x86_64","epoch": 0,"name": "rpm-libs","release": "8.fc17","vendor": "Fedora Project","version": "4.9.1.8"}]}' 'https://example.com/pulp/api/v2/consumers/c1/profiles/'|python -m json.tool
  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
100   812  100   548  100   264    552    266 --:--:-- --:--:-- --:--:--   552
{
    "_href": "/pulp/api/v2/consumers/c1/profiles/c1/rpm/",
    "_id": {
        "$oid": "53b3fed2783d044f47fd9b3c"
    },
    "_ns": "consumer_unit_profiles",
    "consumer_id": "c1",
    "content_type": "rpm",
    "id": "53b3fed2783d044f47fd9b3c",
    "profile": [
        {
            "arch": "i686",
            "epoch": 0,
            "name": "glib2",
            "release": "2.fc17",
            "vendor": "Fedora Project",
            "version": "2.32.4"
        },
        {
            "arch": "x86_64",
            "epoch": 0,
            "name": "rpm-libs",
            "release": "8.fc17",
            "vendor": "Fedora Project",
            "version": "4.9.1.8"
        }
    ],
    "profile_hash": "9afe3bde4abc67de570b1a043c2057c3c8d5cabdfcf3fd3037bb746e25a4a5fa"
}

$ curl -H "Accept: application/json" -X GET -k -u admin:admin 'https://example.com/pulp/api/v2/consumers/c1/profiles/c1/rpm/'|python -m json.tool
  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
100     9    0     9    0     0      8      0 --:--:--  0:00:01 --:--:--     8
No JSON object could be decoded

Version-Release number of selected component (if applicable):


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