Variety Staff Follow Us on TwitterThe official trailer for CBS All Access’ new half-hour animated comedy “Star Trek: Lower Decks” has arrived, and it’s putting an irreverent spin on the beloved franchise.“We’re not really elite — we’re more like the cool, scrappy underdogs,” explains lower-deck Ensign Mariner in the trailer.“We live on a spaceship, nobody is dying from a spear wound!” she exclaims in the midst of some onboard mayhem.The 10-episode series, which has already been renewed for a