By Jailene Cuevas Britney Spears thanked Janet Jackson in an online post before immediately deleting it. The “Hit Me Baby One More Time” singer posted a sweet message about Janet on Instagram on Sunday. She posted a picture of Janet’s cover art of her 1993 album, Janet, thanking the artist for ” keeping” her “dreams and heart alive.” Britney captioned: “Thank you to this beautiful lady for keeping my dreams and heart alive. She’s always been the deepest and brightest woman at the same time.” She continued: “She went through so much but I feel she is someone I will look up to for the rest of my…