A Team Foundation Server 2017 license grants the right to deploy an SQL Server without causing additional licensing requirements. Which edition of the SQL Server may be used?
You may only deploy one instance of an SQL Server Standard without causing additional licensing requirements, with the exception of Team Foundation Server Express which might be used in connection with SQL Server Express. A deployment of SQL Server Enterprise would in any case cause additional licensing requirements, even if it was only used for a Team Foundation Server.
Source: Visual Studio Licensing Whitepaper – November 2016, p. 23