Fix generating migrations with USE_SYSTEM_SQLITE (#40910)

Content.Server.Database/ModelSqlite.cs

@@ -17,6 +17,9 @@ namespace Content.Server.Database
     {
         public SqliteServerDbContext(DbContextOptions<SqliteServerDbContext> options) : base(options)
         {
+#if USE_SYSTEM_SQLITE
+            SQLitePCL.raw.SetProvider(new SQLitePCL.SQLite3Provider_sqlite3());
+#endif
         }
 
         protected override void OnConfiguring(DbContextOptionsBuilder options)