Sentry Issue: [POSTHOG-821](https://sentry.io/organizations/posthog/issues/3707400683/?referrer=github_integration)

Sentry is reporting that when listing session recordings loading persons is n+1

Looking at how the query works 

we 
* load person distinct ids for recordings in the list
* load the persons that have those distinct ids
* create a fict of distinct id to person
* for each of the recordings
    * look up the  person in the dict and pass them to a `PersonSerializer`
    * that looks up the person's distinct ids while choosing Person's `name`
    * (maybe only when there's no email) in order to determine the first distinct id for the person
    
 That final lookup of distinct ids is (**I think**) where the n plus 1 problem is. 
 
 For each person one at a time we go to the DB and get their distinct ids
 
 There's no foreign key from `Person` to `PersonDistinctId` so we can't utilise `select_related` here. 
 
 _maybe_ we can if we use a list serializer for Persons and then combine the two lists
 
 Some of the reports suggest 50% of the time generating the list is spent loading persons
posthog/api/test/test_session_recordings.py
self, snapshot_count, distinct_id, session_id, timestamp, has_full_snapshot=True, window_id=""
    ):
        snapshots = []
        for index in range(snapshot_count):
            snapshots.append(
                {
                    "type": 2 if has_full_snapshot else 3,
                    "data": {
                        "source": 0,
                        "texts": [],
                        "attributes": [],
                        "removes": [],
                        "adds": [
                            {
                                "parentId": 4,
                                "nextId": 386,
                                "node": {
                                    "type": 2,
                                    "tagName": "style",
                                    "attributes": {"data-emotion": "css"},
                                    "childNodes": [],
                                    "id": 729,
                                },
                            }
                        ],
                    },