Does a seasonal job offer a good or bad career opportunity for a fresh grad

I am a fresh grad with a degree in business. I was recently offered a GMS jr. Analyst position at ISS (Institutional Shareholders Services) for a job. I found out later during the interview that it's a seasonal job, meaning the contract will expire in 6 months. I signed the contract when it was presented to me 2 days after. I want to hear your opinions on whether the experience of having this job will be good for future jobs or will it be bad because of the contractual nature. Did I make a mistake accepting this job? I would love to hear your thoughts