Fix typo in error message for IAM service account

[wo-o]

Description

Dear team, I found some tiny typo. Please kindly consider confirming.

Checklist

• Added tests that cover your change (if possible)
• Added/modified documentation as required (such as the README.md, or the userdocs directory)
• Manually tested
• Made sure the title of the PR is a good description that can go into the release notes
• (Core team) Added labels for change area (e.g. area/nodegroup) and kind (e.g. kind/improvement)

BONUS POINTS checklist: complete for good vibes and maybe prizes?! 🤯

• Backfilled missing tests for code in same general area 🎉
• Refactored something and made the world a better place 🌟

[github-actions]

Hello jinnuae40 👋 Thank you for opening a Pull Request in eksctl project. The team will review the Pull Request and aim to respond within 1-5 business days. Meanwhile, please read about the Contribution and Code of Conduct guidelines here. You can find out more information about eksctl on our website

[cPu1]

Well spotted. Thanks for the contribution!

[Himangini]

@jinnuae40 thanks for the contribution, can you please update your branch we will get this merged shortly.

[wo-o]

Dear @Himangini, I update the branch. Please feel free to let me know if there is anything to request.
Thank you !!!