Update README.md

Author: henrymcconville

README.md

@@ -4,6 +4,7 @@ Timeline of changes:
 * 22/05/2023 - All current images are available in the new Docker Hub organisation at https://hub.docker.com/r/githubexporter/github-exporter
 * 30/05/2023 - GitHub repository will be migrated to https://github.com/githubexporter/github-exporter
 * 30/05/2023 - Any new images will be pushed to the `githubexporter` Docker Hub repository only
+* 21/08/2023 - All existing images will be removed from the `infinityworks/github-exporter` Docker Hub repository.
 * 30/08/2023 - The `infinityworks/github-exporter` Docker Hub repository will be deprecated
 
 # Prometheus GitHub Exporter