Fix grammar for countable object (#39251)

Co-authored-by: Sharra-writes <[email protected]>

Author: jsoref

data/reusables/repositories/repo-insights-commit-limit.md

@@ -1,6 +1,6 @@
 {% ifversion not ghes %}
 
 > [!NOTE]
-> Certain contributor, commit, and code frequency insights are only available for repositories that have less than 10,000 commits.
+> Certain contributor, commit, and code frequency insights are only available for repositories that have fewer than 10,000 commits.
 
 {% endif %}