Leomund's tiny hut states :
[...] Spells and other magical effects can’t extend through the dome or be cast through it [...]
The Beholder's Charm Ray states:
Eye Rays. The beholder shoots three of the following magical eye rays at random (reroll duplicates), choosing one to three targets it can see within 120 ft. of it:
- Charm Ray. The targeted creature must succeed on a DC 16 Wisdom saving throw or be charmed by the beholder for 1 hour, or until the beholder harms the creature.
Would Leomund's tiny hut dispell an already active magical effect with a duration such as a beholder's charm ray?