Add delimiter to project stars count

Summary

We should add a delimiter to the project stars count so that it is more readable and aligns with the UI guide

Steps to reproduce

Go to the Explore Projects page

Expected behavior

Instead of 2000 stars, it should say 2,000 stars

Relevant logs and/or screenshots

mentioned in merge request !5741 (merged)

Added frontend label

Status changed to closed by merge request !5741 (merged)

mentioned in commit 146e9059

Mentioned in commit f2220391

mentioned in merge request !14785