If you think summer-to-fall fashion means jeans, think again! Jennifer Garner isn’t slipping into stiff denim yet, and honestly, neither are we. After seeing Garner’s breezy skirt style, we’re rocking her elevated, boutiquey look through October. Garner was spotted heading to church in a modest black sweater, a floral midi skirt and a sleek shoulder bag. The soft, delicate print against a solid knit is a formula that works year-round, and it tak…