LinkField needs fluent's gridfield removed so modal renders

[emteknetnz]

Fluent will add a tab with a gridfield to linkfield, however because there is no react component for gridfield, you'll get a hard error on the frontend and the link modal will not work at all

To work around this on the SPIKE added a workaround protected $schemaDataType = self::SCHEMA_DATA_TYPE_STRUCTURAL;, though this shouldn't be merged as the lack of a gridfield component should hard fail so that developers are prompted to remove gridfields

Acceptance criteria

• When fluent is installed, the tab with the gridfield is removed so that it does not render in the link modal

PR

• FIX Remove tabs with only gridfields #247

[GuySartorelli]

PR merged