Julia Garner is one of Hollywood’s brightest stars, thanks to major roles in “Ozark” and “Inventing Anna” that have cemented her in that pantheon. However, though you’ve probably heard of Garner if you’re a TV fan, you may not know her husband, Mark Foster, who is more than just the guy sitting next to Garner at every award show — he’s also a very popular musician.
Foster is best known for being the lead singer of the band Foster the People, which he formed in 2009 with his friend, drummer…