[Wyscout v2] Fix keeper save coordinates

[probberechts]

The start coordinates of goalkeeper save events should be retrieved from postions[1] and inverted for the keeper's own goal.

{
            "eventId": 9,
            "subEventName": "Save attempt",
            "tags": [
                {
                    "id": 1209
                },
                {
                    "id": 1801
                }
            ],
            "playerId": 3429,
            "positions": [
                {
                    "y": 0,
                    "x": 0
                },
                {
                    "y": 43,
                    "x": 11
                }
            ],
            "matchId": 2058007,
            "eventName": "Save attempt",
            "teamId": 5629,
            "matchPeriod": "1H",
            "eventSec": 1834.504524,
            "subEventId": 91,
            "id": 261446311
        }