There is no disadvantage on the spells that require saves, only on attack rolls.
Since the drow racial abilities synergize well with being a Charisma-based caster, sunlight sensitivity is not such a harsh penalty as it might seem initially.
You can get around the penalty by playing a caster with cantrips and spells that do not require an attack roll, but use a saving throw instead, and use those when under the penalty.
As an example, a bard could use with Vicious Mockery, a sorcerer Acid Splash or Poison Spray and a cleric Sacred Flame.
The darkness spell mentioned in other answers might help too, but is generally too harmful to your own party to be of general use, even as a Warlock with Devil's Sight.
Finally, as mentioned in a comment by @sadaqah, Drow get Faerie Fire as racial spell once a day and can use it to (potentially) negate the sunlight disadvantage.