formatter: support goimports-reviser, passing in file path

[iacore]

https://github.com/golang/vscode-go/blob/36d95e2eab1c68be2445798f6a4ff76601af4b8c/extension/src/language/legacy/goFormat.ts#L50-L52

    "go.formatTool": "custom",
    "go.formatFlags": [
        "-format",
        "-rm-unused",
        "FILENAME, supposedly",
    ],
    "go.alternateTools": {
        "customFormatter": "goimports-reviser",
    },