Travis Kelce revealed how his girlfriend, Taylor Swift, felt about his brother, Jason Kelce, taking off his shirt and stripping down during the Chiefs playoff game on Sunday, January 21. While chatting, Jason, 36, confirmed that his wife, Kylie Kelce, had warned him ahead of time to not do anything silly, as this was the pair’s first time interacting with the pop star, 34. “She was already telling me to be on my best behavior because we were meeting Taylor,” he said on their “New Heights” podcast. “So she’s like, ‘Do not … be on your best behavior.’ I was like, ‘Kylie the first day I met you…