Problem in grading.yml file

[Sterling463]

While working in the exercises for ghas, I noticed that the grading.yml file would not run because of a spacing issue on line 29. This issue was noticed in multiple exercises. The grading action worked as expected once I removed the extra space. For reference, including a link to one of the PRs I opened to fix the issue: githubtraining/exercise-configure-codeql-language-matrix#3 (comment)