Rate limiting in shell scripts needed

[leontebbens]

There is a solution for #9, however the shell scripts in folder shell_script also lack rate limiting.
My solution is to add "sleep 1" after the PUT curl:
curl -s -X PUT -H "Authorization: bearer $api_key" -H "Accept: application/vnd.github.london-preview+json" $enable_url
sleep 1 #rate limiting to prevent blocking by github server

In both shell scripts

[leontebbens]

I've made a pull request

[jhutchings1]

Thanks @leontebbens ✨ I reviewed and merged your PR.