github/workflows: mention website maintainers in commit

Do a mention in the automated commit, so it sends a notification to the
website maintainers. So, they can open a pull request with this commit.

Signed-off-by: Ivan Valdes <ivan@vald.es>

scripts/update_release_version.sh

@@ -55,6 +55,8 @@ git add "${index_file}"
 git -c user.name="${git_author}" -c user.email="${git_email}" commit --file=- <<EOL
 [${release_minor}] Update installation version to latest tag (${new_version})
 
+cc. @etcd-io/maintainers-website
+
 Signed-off-by: ${git_author} <${git_email}>
 EOL
 git push "${git_remote}" "${branch}"