Fix redirect URI formatting in README after recent changes

[JoaoZPalma]

Correct the redirect URI format in the README.

[JoaoZPalma]

Was all happy cuz i got the Spotify to connect to Emacs but now its giving me:

Log

smudge connected
url-retrieve-internal: Bad url: d3a97b8e006a4eb98fffe9c2bdecaa1a
Error running timer ‘smudge-controller-player-status’: (void-function smudge-connect-player-status) [2 times]

Not from my change, mine its merely the ReadMe

[girishmm]

This has been mentioned in #105. Would be nice if you can add this to your PR :)

Also, to make the URI fully compatible with new Spotify regulations, localhost must be changed to 127.0.0.1 as mentioned in #101 and #102

[JoaoZPalma]

Thank you @girishmm, I changed localhost to 127.0.0.1 locally but completly went over my head at the ReadMe, also added that change in #105

Didn't have time to test it out tho, whoever is checking out this pr please take it with a grain of salt

[danielfm]

Thanks!