Drop support for MS SQL Server

Sequelize generates invalid SQL for the 'fix-enum' migration from 2018.
Since nobody has complained about this issue since then, we can just
drop support for SQL Server.

Signed-off-by: David Mehren <git@herrmehren.de>

package.json

@@ -97,7 +97,6 @@
     "sqlite3": "^5.0.0",
     "store": "^2.0.12",
     "string": "^3.3.3",
-    "tedious": "^6.6.0",
     "toobusy-js": "^0.5.1",
     "umzug": "^2.3.0",
     "uuid": "^8.0.0",