chore(docs): Add site The COVID Tracking Project (#22828)

Co-authored-by: LB <laurie@gatsbyjs.com>

docs/sites.yml

@@ -10260,6 +10260,17 @@
     - Food
     - Marketing
   built_by: Tyson Foods, Inc.
+- title: The COVID Tracking Project
+  url: https://covidtracking.com/
+  main_url: https://covidtracking.com/
+  source_url: https://github.com/COVID19Tracking/website
+  description: >
+    The COVID Tracking Project collects and publishes the most complete testing data available for US states and territories.
+  categories:
+    - Media
+    - Healthcare
+  built_by: The COVID Tracking Project Web Team
+  built_by_url: https://github.com/COVID19Tracking/website/graphs/contributors
 - title: The Gauntlet Coverage of COVID-19 in Canada
   url: https://covid19.thegauntlet.ca
   main_url: https://covid19.thegauntlet.ca