Code Insights: [BE] Strange behaviour of insight date when drill-down filters have been applied

Created by: vovakulikov

At the moment it seems like UpdateLineChartSearchInsight mutation doesn't work if we provide some filters in there (see gql error in steps to reproduce section). Also after any updates (via drill-down filters or via edit page) insight becomes in processing mode. Even if we change something like title or search query color or drill-down filters.

Insight after any updateInsight mutation

Steps to reproduce:

1. Go to any backend insight
2. Type some value in any field of drill-down panel form.
3. Click on save filters button
4. See gql errors about mutation

GQL mutation input data

{
    "input": {
        "dataSeries": [
            {
                "query": "FunctionComponent",
                "options": {
                    "label": "Function component",
                    "lineColor": "var(--oc-indigo-7)"
                },
                "repositoryScope": {
                    "repositories": []
                },
                "timeScope": {
                    "stepInterval": {
                        "unit": "WEEK",
                        "value": 2
                    }
                }
            }
        ],
        "presentationOptions": {
            "title": "Add insight 1.1 Test"
        },
        "viewControls": {
            "filters": {
                "includeRepoRegex": "",
                "excludeRepoRegex": "sourcegraph"
            }
        }
    },
    "id": "aW5zaWdodF92aWV3OiJzZWFyY2hJbnNpZ2h0cy5pbnNpZ2h0LmFkZEluc2lnaHQxMVRlc3Qi"
}

Errored response from the BE

{
    "errors": [
        {
            "message": "graphql: got nil for non-null \"InsightView\"",
            "path": [
                "updateLineChartSearchInsight",
                "view"
            ]
        }
    ],
    "data": null
}