insights: duplicate time values are returning from API [timeboxed]

Created by: coury-clark

When clicking on an insight point the wrong query was generated. @vovakulikov identified that the API response is returning duplicate values for a single time period.

Typically we deduplicate data coming out of the database, so my first instinct would be to look at the resolver construction and see if there is any duplicates there.

Relevant insight https://demo.sourcegraph.com/insights/insight/aW5zaWdodF92aWV3OiIyNU9UM0FkT2hSem1reHJxbWFKZE9Qekt5VUUi

{
    "data": {
        "insightViews": {
            "nodes": [
                {
                    "id": "aW5zaWdodF92aWV3OiIyNU9UM0FkT2hSem1reHJxbWFKZE9Qekt5VUUi",
                    "dataSeries": [
                        {
                            "seriesId": "25OT3D2PbaSBv2w4o3QQEf5oZV0",
                            "label": "this.skip() or it.skip(",
                            "points": [
                                {
                                    "dateTime": "2021-06-20T00:00:00Z",
                                    "value": 12,
                                    "__typename": "InsightDataPoint"
                                },
                                {
                                    "dateTime": "2021-07-20T00:00:00Z",
                                    "value": 12,
                                    "__typename": "InsightDataPoint"
                                },
                                {
                                    "dateTime": "2021-08-20T00:00:00Z",
                                    "value": 14,
                                    "__typename": "InsightDataPoint"
                                },
                                {
                                    "dateTime": "2021-09-20T00:00:00Z",
                                    "value": 12,
                                    "__typename": "InsightDataPoint"
                                },
                                {
                                    "dateTime": "2021-10-20T00:00:00Z",
                                    "value": 12,
                                    "__typename": "InsightDataPoint"
                                },
                                {
                                    "dateTime": "2021-11-20T00:00:00Z",
                                    "value": 12,
                                    "__typename": "InsightDataPoint"
                                },
                                {
                                    "dateTime": "2021-12-20T00:00:00Z",
                                    "value": 22,
                                    "__typename": "InsightDataPoint"
                                },
                                {
                                    "dateTime": "2022-01-20T00:00:00Z",
                                    "value": 22,
                                    "__typename": "InsightDataPoint"
                                },
                                {
                                    "dateTime": "2022-02-20T00:00:00Z",
                                    "value": 24,
                                    "__typename": "InsightDataPoint"
                                },
                                {
                                    "dateTime": "2022-03-20T23:13:23Z",
                                    "value": 32,
                                    "__typename": "InsightDataPoint"
                                },
                                {
                                    "dateTime": "2022-04-20T23:13:40Z",
                                    "value": 32,
                                    "__typename": "InsightDataPoint"
                                },
                                {
                                    "dateTime": "2022-05-20T23:38:10Z",
                                    "value": 77,
                                    "__typename": "InsightDataPoint"
                                },
                                {
                                    "dateTime": "2022-05-20T23:38:10Z",
                                    "value": 77,
                                    "__typename": "InsightDataPoint"
                                },
                                {
                                    "dateTime": "2022-06-16T00:25:13Z",
                                    "value": 58,
                                    "__typename": "InsightDataPoint"
                                }
                            ],
                            "status": {
                                "backfillQueuedAt": "2022-02-20T22:58:34Z",
                                "completedJobs": 7,
                                "pendingJobs": 0,
                                "failedJobs": 548,
                                "__typename": "InsightSeriesStatus"
                            },
                            "__typename": "InsightsSeries"
                        }
                    ],
                    "__typename": "InsightView"
                }
            ],
            "__typename": "InsightViewConnection"
        }
    }
}