Use bg-info instead of role-tertiary for cluster count badge

[rak-phillip]

Summary

This uses bg-info instead of role-tertiary for cluster count badge.

Fixes #15669

Occurred changes and/or fixed issues

• Use bg-info instead of role-tertiary for cluster count badge

Technical notes summary

role-tertiary is a button style and is not a known variant of a badge.

Areas or cases that should be tested

• Home Page cluster counts

Areas which could experience regressions

• NA

Screenshot/Video

Checklist

• The PR is linked to an issue and the linked issue has a Milestone, or no issue is needed
• The PR has a Milestone
• The PR template has been filled out
• The PR has been self reviewed
• The PR has a reviewer assigned
• The PR has automated tests or clear instructions for manual tests and the linked issue has appropriate QA labels, or tests are not needed
• The PR has reviewed with UX and tested in light and dark mode, or there are no UX changes
• The PR has been reviewed in terms of Accessibility
• The PR has considered, and if applicable tested with, the three Global Roles Admin, Standard User and User Base